Firstly, look at it this way, a kid tells his parents he wants a new video game for his PC/Mac. The parent agrees and drives to the store and buys it and or picks it up while they happen to be out in the streets shopping. That's the real world. The parent is not going to go online searching for websites that host online game downloads for a better price such as Steam, that's just not realistic.
Secondly, just what proof do have that COD4 is "widely known" to be 1/10th of the price? If it was so "widely known" the retailers wouldn't be trying to get a much higher price for it. Just remember, you as well as me as well as everyone else have been a "sucker" as you call it at one time or another when making purchases.
herpaderp. Read my comments. I was talking about Civ 4. It was widely known on the internet, the same place where you would have heard about the game initially. You don't have to search. It's the same amount of "searching" as finding out the game exists. The internet is just as much "the real world" as stores are. There's nothing unreal about it. It's just another facet of it.
Retailers don't care. Valve sets their low prices because they can. Retailers don't lower them because they rely on suckers to buy their products. They can't let their products be marked down that low because they have to have a profit margin. They rely on suckers. Me? I don't buy crap usually. When I do, I'm very methodical. Sorry.