I can only really think of one game that I flat out quit as a player, though there have been several that I just allowed to die as either a player or a GM.
A friend of mine and I were invited to play with a group of people we had never played with before, and from the outset it seemed fine. All books were allowed, and we could make any character we wanted, but it was going to be a viking-esk campaign. I made a Valkyre-Bear-Viking themed character, mechanically a stalwart battle sorcerer with designs on going into Exalted Arcanist and Sentinel of Bahari. The GM said that was fine, and he liked the idea. My friend made a piratical Dwarf named Saltbeard; I think he was going for Dread Pirate. The day before the game session I was informed that I wouldn't be able to get into 2 prcs, because 2 prcs was 'too overpowered.' I tried to tell him that my character wasn't overpowered, and that the strength of a character depends more on WHICH prc you had, not how many. He'd have none of it, and I had to change my character if I wanted to play. So I switched my character to a Sorcerer/Incantatrix instead, which made him happy because it wasn't 2 prcs, whatever. The day of the game, he told my friend that his dwarf couldn't be named Saltbeard, because there were no sea-dwelling dwarves, and he had to change his name.
At this point, both my friend and I got rather upset, because dammit, if the Dwarf wanted to be called Saltbeard, even if it wasn't his birth name, he should be able to be called Saltbeard. Its a fine dwarfy name. Again, the GM essentially laid down an ultimatum: if we wanted to play, the name would have to be changed, because there couldn't possibly, EVER be a dwarf named Saltbeard in this game. Very upset, we decided to give the game one session, since we were already there.
The very first thing in the game had us tossed into a pitched battle between Vikings (who were our allies) and a land-lubing group. The GM turns to me and tells me that since I'm the party mage, he expects me to deal with most of battle, and it should be fairly easy. I blink at him a few times, write it off as nothing, and cast a non-lethal fireball into the largest group (I had a focus in metamagic so I was packing a bunch of weird feats that I planned to use with Arcane Thesis with Wings of Flurry when we got to that level, we were only level 6 though. Being a good character, and not really understanding the whole combat situation because we received no backstory, I figured it was a reasonable course of action.) The GM went off about since I didn't specify I was only aiming for enemies, the roaring flames engulfed the soldiers and vikings alike, and they screams of agony fill the air as they die horribly, at which point I remind him that it was a non-lethal fireball. He ignores me and starts talking about the viking leader turning on me, axe in hand, demanding to know why I killed so many of his men, to which both my firend and I say at once "IT WAS A NON-LETHAL FIREBALL." To which the GM responds, "Huh?" And I show him my character sheet and the book I got it from. He then asked all the other players if they had heard me say that it was non-lethal, and they all say yes, they had, and then I point to my blurb of a character backstory, which says I refrain from lethal violence as much as possible. He finally caves and lets the non-lethal fireball pass, and has the vikings all run up and coup-de-grace all of the unconscious enemies.
To which I think, oh well, it must be really important that those enemies die. Only no, its not important at all, because those enemies and the viking allies we had were never mentioned again. After that we got into the real heart of the GM's style. You see, he already had everything planned out. And I'm not just talking about railroading, but the results of every single action was already decided before dice were rolled. To wit, as a sorcerer, I had bad to hit and bad AC; I was a bookish, weak character who is good at spells. The party fighter was a strong brute that's good at hitting things. My friend was a sneaky rogue who was good at attacking from shadows, but not good at fighting otherwise. That was all nice and all, only I was a stalwart battle sorcerer with primarily self buffs to help me in combat and 18 strength. The party fighter was something like a drow fighter, high dex and light armor, and was mainly focused in tripping and disarming. And my friend was a flanking focused rogue, because he saw we were mostly melee oriented. We had a fourth player who was forced to play a divine caster because we needed 'party balance,' but I don't remember them much. What I do remember is getting into a one-on-one fight with soldier, and to the GM's surprise, I tried to attack him with a weapon! I rolled a 19, to which the GM immediately announces I missed, and moves on to the fighter, who hits a different soldier on a 12. Since for me, a 19 is a 27, I ask what armor the enemy is wearing, and the GM says standard chainmail. Already realizing what was up, I reminded him about my total bonuses from strength, and how I had a rogues BaB, to which he didn't really listen. So the next round I cast true strike (after being beat on several times, he didn't say their attack rolls and never asked for my AC, I figured at the time they rolled high, but now I think otherwise) and then the round after that, I attack, and roll a 14 or something, to which he says I miss again. I remind him that True Strike is a +20 to hit, to which he says "Oh, then I guess you hit then." Meanwhile the fighter is going fine with average rolls, and hasn't been hit once despite our AC being about the same.
After the fight, we get to do some roleplaying, and the GM ignores us and talks to someone who wasn't even playing, just happened to be hanging out. Whatever. I manage to convince the group with liberal use of prestidigitation and some other nifty spells that I was a minor deity, sent to lead them to greatness in battle. We then sat around for while waiting for the GM to get back to the game.
After that, we had one more fight against a big monster. The fighter swings at it, trying to trip it, and rolls low. "Oh, I probably missed, I got a 14 total." "Oh no, its big and slow, you hit it fine. Roll damage." "Actually, I want try to trip it, I get a..." "Its too big to trip." "I'm going to try anyway." "Oh, well... *rolls dice* Nope, you can't trip him, he's too big." "Okay..." I'm up, and I go to hit the creature. I roll a 10... "Oh, you missed. You should really try casting a spell." "With my bonuses, I got an 18, that's higher than the fighter." "What? Let me see your character sheet... why is your strength so high?" "Because this is what I do, I hit things with a spear." "Umm... okay, I guess you hit then." Rogue's turn, he tumbles around for flanking, and attacks the creature's back. "Well, you hit because of flanking, but you don't get sneak attack." "Really? Why not?" "Because you only get sneak attack from the shadows." "You get sneak attack from flanking too." "Err, what I mean is that you don't get flanking on this creature, so you don't get sneak attack." At this point, we were getting pretty exasperated (there had been a lot of other stuff that I can't remember) so my friend gave up and let it go.
The final straw was in the next room, however, where we met an npc dwarf that was supposed to guide us to some treasure or something. He informed us of the backstory of the dungeon, and the war, and all of the other setting stuff, just a giant plot dump basically. At the end of all of which I ask the dwarf his name. "Umm..." The GM pauses, and it becomes obvious that he never figured anyone would ask such a basic question. Suddenly, he gets this huge $%&*-eating grin, and says, "I'm Saltbeard, the sea dwarf." My friend and I stood up, and without a word, left the table.
