Right now they're probably doing this all out of pocket as "start-up"...so they're trying to cover some of their fees with the processing fee, and want people who are active, not just people who are going to sign up for a referral and never do anything with it. I don't really like the "inactivity" fee, but it won't effect me because I like my bonus button even if there are no opportunities at the moment. The past couple days I've made more on their bonus button than I did with my own spins at SuperPoints.
Once they have more paying partners they will probably get rid of the processing fee.