Facebook is the way forward, pop the game you want to sell on the news feed....BAM see who replies...if that fails then trade it in at Game or gamestation

Convenience

because its easy

out of 26 second hand buys on marktplaats I've been scammed twice for a total of 50 euros. That is really just a 2 euro premium I guess.

for selling it's perfect though :)

I buy and sell the majority of my games through markplaats nowadays.

In the case of Gamestop, depending on the special offers going on sometimes it's really worthwhile. A couple years ago I gamed the system there by trading in a bunch of ancient PS2 games that I probably wouldn't have gotten more than $75-$100 for on Ebay and ended up with over $150 in store credit.

It's ease mainly. Myself, on the rare occasion I trade in a game, I use Amazon or Ebay.

Because it's easier.