It is just people in general now. It is disappointing. I was hooking up a guy locally with some old duplicate games I have. I was giving the guy 50% of ebay pricing and sometimes even less. He was buying up everything I had. I then realized he was reselling the games for a lot more to other people. I told him I would keep selling stuff through him, but I wanted more money (since before I thought I was just helping a fellow collector). The guy flipped out and said I was greedy and then his wife called me later and told me how I had ruined her husband's life. It was straight up crazy.
If his life was truely ruined by you refusing to let him continue to exploit you then that's his problem for being a grade A douchebag.
This type of thing I have a very low tolerance for.
At the other end of the spectrum I sometimes struggle with the "flip it" mentality too. If I know you got Earthbound for $1 and it's the fifth one you've picked up that year I have a hard time bringing myself to pay more than original sale price (I mean the price the game cost at its original release) for the item. I understand market value and time/effort invested, etc. But part of it was simply luck. If I've been lucky I like to share that with fellow collectors that haven't been so lucky.
I've had folks on here hook me up. One guy sent me a copy of Shatterhand for free out of the blue just because he found it cheap and saw it in my wishlist (it's a $70 game right now).
The same guy hooked me up with a first print of Bayonetta 2 for the price he got it (which was half of the going rate on eBay).
For the record theflea has been pretty good to me. I've added a handful of things to my collection thanks to good (cash) deals with him.
I think it's okay to ask for what you think is fair and acceptable as the seller and it's fair to walk away if you feel it's too steep as a buyer.
I guess it's haggling I'm no good at because the way I see it typically the haggler is more often trying to con someone into a lower price just to benefit themselves. Rarely have I seen someone haggling to get something at a fair price or to correct the overpricing of an item.
That said, we've all haggled at sometime to try to tip things further in our favor. So maybe our angst with it is hypocritical?