See that $10 contest at the top? That's got $50 in entry fees, and will pay the top 3 a total of $90. This is called an overlay. If you were to jump in for $10, there would still be a 50% overlay. You would need to be pretty bad at this to lose long-term in contests with this much free money. You can also see ID=26 running with just two entries. In that one both players automatically won, and were just fighting it out for the 1st place prize. A third player would have made things a bit more interesting.
As we ramp this site up, you will probably see lots of this over the next few weeks. Check back ten or so minutes before the start of contests, and grab yourself some free money!