Infinite planes means hyper inflation. That's why I specified that my planes set up is no longer infinite. All it takes is ONE wizard to use Wall of Iron and melt it down over and over again to cause it. It takes ONE wizard binding an Efreet and wishing for gold (and yes, gold, not money). ONE wizard using Fabricate on the piles of gold and iron he has, making them into very valuable things. Then you have hyper inflation, and everything sucks forever because this version of hyper inflation is irreversible and infinite. Making the planes infinitely large makes it worse, since now you are guaranteed to have a wizard doing this. Guaranteed to have an infinite number of wizards doing this, in fact. If you're a 12th level wizard (of which there are an infinite number in the planes, given that they are infinitely large), you have the means to cast Wall of Iron and then move/melt/shape it using magic, which removes your work argument.
*Although, when you cast a spell like that what you are effectively doing is converting arcane energy into matter via something similar to E=MC^2, but this would ultimately result in the the universe running out of arcane energy if the result was permanent. This is equally bad, as wizards would ultimately turn to other energy sources for their spells (such as corruption magic in the Dark Sun setting).
In order for this to be true, the energy has to come from somewhere else, and then the energy needed to cast and carry out the spell. So you need to pull enough energy to make all that matter (which would pretty much require turning an equal amount of matter directly into energy, and then back again) to make it work. There's no getting around it, conservation of energy is a problem. Oh, and keep in mind, this is D&D, so physics may not apply as well as it does here....
OK, so, if you remove all the 'creation' spells which result in matter being permanently brought into the universe from nothing* or ruin the game economy, and make spells like create water/food transmutation spells require an equal if not greater amount of materials to cast and are high level spells so most wizards wouldn't bother casting them unless they were desperate (transmuting lead to gold would require vast amounts of effort for little gain and bring the wrath of the gods on you). Then you can start to create a somewhat respectable economic system, although this still leaves spells like fabricate a potential breaker (maybe place tighter restrictions on these spells?).
Spells like Create Food/Water would not exist same as other 'creation' spells. But all of these can still exist, it just requires modification. Summoning/calling the food works, and spending equal energy works (but see above). As for Fabricate? All that does is remove the time aspect of fabrication. You still need the skill, and energy to move stuff. I think maybe we can say that one difference between our universe and the D&D verse is that energy of motion is greatly reduced? Say, 1/2mv^.5?
Unless of course the healer in question receives his abilities from a divine source (which most would), in which case if he decided to charge huge prices for a service such as healing the sick then he would likely have is powers cut off (not really lawful good if you charge more than an entire years income for casting Remove Disease once, since you are clearly serving yourself without regards to others). That's not to say however that he wouldn't turn away those who he deemed not needing to be cured and would perform the service for free (would most likely take a donation for his church). For higher level spells like Resurrection he would obviously charge very high prices for as the people who would be needing a spell like that would be wealthy and taking vast amounts of money from them would be seen as just provided it was used further the work of his deity.
As you said, the service would no be provided free of charge. He has to make a living, but it would almost certainly be a non-profit. Private physicians, on the other hand, would charge more, since they would provide better service. Keep that in mind too, they are performing a service. I do recommend making healing spells more significant and having them require an expensive component (a focus is already required, but maybe a touch of diamond dust (1 sp worth?)) for the status effect eliminators. Eschew Materials also kind of has to go, but that's not a big problem, since spell components would be very inexpensive. These are the arcane materials being used (and remember, they are matter being converted directly into energy in most cases, that's where the energy is coming from).
