After PC's have raided a few dungeons, and they've brought back thousands of gold pieces to the local village, does anyone every have inflation occur? I think it would be interesting if it did. I can see the look on the players faces if they come back and suddenly the inn rooms are 50 gp a night, instead of 1 gp. Particularly if this rate applies only to them.
It would actually make a lot of sense for this to occur. There is no Better Business Bureau, so who's to regulate the prices? If all the various innkeepers, craftsmen, and merchants start talking with each other, I could definitely see them coming to an agreement about a new pricing structure for the PCs.
Even in the modern world, poor people can be charged differently than rich people. Doctors are particularly famous for doing this. So why not have it happen in a fantasy setting?