That is true as a couple of the games I got for $20, hell I even managed to get Bioshock and the sequel for just $40 thanks to a coupon.
The only games I actually bought full retail had been Demon's Souls, Bayonetta, Valkyrie Chronicles and Disgaea 3. The rest were through friends in the retail business giving me a discount as well as coupons through bestbuy that would take $20 to $30 off the original price. Not to mention I waited on a couple of games to get cheap.
I will say my worst purchase ever had been "Alone in the Dark" for the Wii ONLY because I was half drunk that time and wandered into a walmart that afternoon with friends.