I'd like to see figures on how long people stick around when they've bought their way to the top. I know from experience that cheating through a (singleplayer) game makes it get old and boring rather quickly. I'd imagine the same would hold true for MMOs.

You would think so. But then, MMOG players are a strange lot. Look at the macroers, for example. I remember when it was really bad in AC, you'd have people macroing non-stop in order to get to level 120+ and thinking what's the point. How could they be having fun and yet it went on and on. Then they'd breeze through whatever new content was added and go back to macroing until the next patch came, month after month after month.

Actually, I'd guess that more people who play “normally” quit in a given period due to boredom than the ones who “cheat”.

You do make a good point. A lot of people who play MMOs play to be on top. They like the social aspect because there are other real people who they are seemingly “better than”.

The thing is, I think these people are not a majority. I'd venture a guess that the average buyer of in-game items is not one of these people. Rather, they are like you or me but are less willing to spend time to get things.

So maybe they are going to quit anyway... maybe buying things lets them stick around slightly longer, instead of giving up. I don't know.