I guess it's just the drive of being the strongest, or the richest, or whatever the goal of the game is. It's pretty satisfying to see your name on some sort of leaderboard. The text based nature doesn't bother a lot of people even now. The real problem is making a game that's fun, and that's the hard part.
I just realized, we're all on a text-only site and getting onto the "leaders" page was a big motivator for me for a short while. Perhaps I should quit throwing stones in my glass house.. :)