I have to play on a budget, so I do try to be fair when it comes to prices. I'll shoot someone an offer if I think their prices are high or sometimes I straight up tell them what I can afford at the moment. What really gets me is that an offer is made, alot of people do not know how to counter offer. Seems like bartering is starting to become a lost art.
The only other thing that really gets me is looking at my local craigslists and seeing all of these different spyders (clones as well) and tippmanns for outragious prices. The paintball market in this area blows as far as old school goodness is concerned.