There is also a legal principle of conscience, particularly of faith, and a right to refuse service, which is older.
Citation Needed. Indeed, one of the big breaks with previous legal regimes is the First Amendment and Freedom of Religion. But, honestly, that's neither here nor there. Nobody in existence rates legal rights based on their age. As you're obviously aware this right to refuse service, as you put it, has a number of strict limits. It's by no means general. It does not support your argument, especially in whatever tenebrous state it currently exists in American law.
While I mentioned the age of some legal provisions, that principle is in no way presently cabined to inns. So, while your remarks may have been persuasive to a judge in the 16th century, I thankfully do not live then. Somehow, we've had expansive legal developments in the past 500 years. These provisions have been extended to various firms and business. So, try again. And, if you choose to, try to base it on what the law is, rather than what you'd like it to be.
Even with this, a baker refusing a birthday cake for a gay couple has a significant difference from refusing a wedding cake.
How so? And, a wedding cake was my exact hypothetical. The original question was about gay marriage, though, not about rights of refusal for service of civil rights. Like I said, you've conflated the two, they are entirely different legal and moral questions. But, I guess we're down this road.
On this point you'll need an argument that does not amount to "this offends the baker's religious sensibilities and therefore they cannot be compelled to do it." That has been conclusively foreclosed by numerous other constitutional and legal commitments; courts have been at pains to point out that the free exercise of religion, an important and fundamental right, is, like all such rights, not absolute. We've got 100+ years of precedent on this.
You also cheat in the lesbians making out in the car example. You contrast a taxi cab (which I guess had to deal with the state action doctrine?) with
a hypothetical Uber company policy that would apply generally and not discriminate against anyone on the basis of sexual orientation. A general "no public displays of affection" policy obviously applies to queers and straights alike.
As for more direct preference, note the difference in how corporations that support or oppose non-heterosexual, non-monogamous marriage are treated differently. Likewise consider when the last time you heard about a corporation making a PR announcement that it had hired a monogamous, married, heterosexual as opposed to when it hired some other version.
So, the idea that corporations make a
choice to trumpet some forms of diversity implies legal or rights imbalance? How could that possibly be so? This is an absurd statement.
Equal treatment before the law =/= equal popularity before the public. Why would it? The Nazis get to march in Skokie, just like the League of Awesomeness that Everyone Really Really Likes. The former is one of the most maligned groups in existence, the latter (admittedly fake) isn't.
If you beef is with civil society and the attendant popularity contests, then you were not responding to Bhu's point and are seeking to change the goal posts now.
Clearly there are very functional circumstances when a "married" gay couple is treated better than other married couples.
And I will calmly wait for you to identify one where the gay married couple has different, and greater, legal rights, privileges, etc. than a straight one.
P.S.: with the caveat that I am presuming we are talking about the US you don't get to put scare quotes around marriage for gay people. If Adam and Steve go to the county clerk and get a certificate (or common law marriage, etc., depends on the state), they are just as married as Ted Cruz and Heidi Nelson. For better or worse, in the United States the government gets to decide who is married and who isn't. If you want to put some qualifier on it, like "religiously married" or "Catholically married" or "married before god" then go ahead.