Well the issue is that you are in direct competition with calc contests like the UTI one, Omni, TI-BANK and earlier the Cage Matches. Most people around here are more into game creation for calcs but doing a calc game contest wouldn't work well because there are always other established contests going on, not to mention in most cases people prefer having big prizes. Even Cage Matches started to die at the end, as barely anyone would vote anymore.
This is probably why less people are interested.