[quote name='MSI Magus']Why not buy it, flip it then rebuy it later? I like to keep most of my games too, but its a smart stratagy. I can think of a lot of games like Super Mario Galaxy 2 and Uncharted 2 that I did this with. Buy em, get the $20 credit, play it, flip it for $35-$40 then rebuy when I see a $10-$15 copy.[/QUOTE]
It's mostly because I'm lazy/busy (in that order).
If I bought it at launch, I would feel pressured to play it right away so I could flip it while it still had good value. If I just wait until it's $20, I can get it and play it at my leisure. I still have sealed $20 games on my shelf waiting to be played, but it doesnt' bother me because rarely do I see those games go lower than the price I paid for them.
I work long hours, but I make decent money so it's not imperative that I squeeze all the value I can out of my purchases. When I was younger I used to buy from one place, trade in to another, and do everything I could to stretch my gaming dollar. Now I can barely find time to play the games, let alone finish them quick and trade em back in when I'm done. lol