Inflation caused by PCs spending loot is funny as hell. I remember doing this to players once, and they become progressively more and more disgruntled as everything started to cost wheelbarrow-loads of cash. In fact, the players' behavior was part of what catalyzed the collapse of the gold standard and the invention of paper money in one of my campaigns.
With 3E, though, you sometimes think this has already happened.
I mean, seriously. Doesn't anybody think it's kind of silly that even a mid-level character will be equipped with items with a net worth in the tens of thousands of gold pieces, a quantity which weighs hundreds of pounds? For example, a 30000gp galley, comes down to some 600 pounds of gold pieces. If we figure half of a gold piece of actual GOLD, that's some 300 pounds of gold. How would you even CARRY this much money?
I'm pretty sure I can buy a stinking boat for less than my weight in gold.