I don't have a particular problem with people charging what they want for their games. If it sells, then it was priced correctly. While I think getting a deal on a machine makes it easier to pay it forward, it's certainly not mandatory, since I've gotten screwed lots of times and prospective buyers aren't going to overpay just because I did. Buyers and sellers seeing eye to eye on price is what makes a market.
I do have a problem with the liars, particularly those who are intentionally misrepresenting something in order to pad their wallets. I have observed that people like that tend to get what's coming to them sooner or later.