I have heard a lot of chatter from challenge coordinators, blog dt's, etc. that prizes seem to be what gets people to play in the challenge. SCS has dropped off in participants, I know vsn used to get a ton of players when there were prizes involved & now there aren't too many people that play. It seems to be the hostesses & the same faithful ones. Stamptv also took a hit when the prize changed to a grab bag & not a choose your own.
There are a lot of challenges out there also & that makes a difference.