Wait until you see the drop off this year, starting it later. Of course, I guess that increases the odds of the hard-core contest guys, so thanks, Joe.
Seriously, though, my guess would be a combination of guys who legally can't win the money and "life". For example, the commissioner of my main league is a subscriber. He's knowledgeable and active, and spends lots of time doing his Commish duties, in addition to following all the normal FF developments. Traditionally, we've compared rosters on the league chatboard and followed each other's teams (along with 2 or 3 other guys there who are subscribers). Two years ago when I posted my roster, his response was "oh, crap, I was so busy, I forgot to get my entry in." Last year, I jokingly sent a reminder a few days before the deadline, more to rub in the fact that he had forgotten than to actually remind him. His response? "Wow, thanks! I threw together a lineup when it first came out, then got wrapped up in other stuff and forgot to get back to it. I'll do that now."