That reminds me of a fallacy that was described somewhere (is it in freakonomics?). A daycare place wanted parents to not be late for pickup so they instituted a small fine ($5-10) if you pick up late. The result was: more late pickups, because it now had a price, the perception changed to make it less shameful and more like the price of a service.
So, on top of paying for a gym membership and not using it, you're paying an additional $10 for each time you should go but don't, and it's... still a good deal?
But of course! Since when are human beings perfectly self-consistent? The part of me who wants to sign up for a gym membership is concerned with long-term planning, and thinks it would be a good idea to remain healthy into older age; the part of me who actually has to go to the gym, here and now, feels far more concerned about the fact that working out sucks, and would very much rather do just about anything else.
Just to be clear, it's not necessarily $10 each time you don't go. You set yourself a target like "4 times this week" or "10 times this month" and it's when you fail to hit your own target that you lose the money.
It took me a minute to work through why I hated this so much. What it comes down to is that <politician I loathe> is actively doing harm. Even if you don't believe that it's essentially gamifying something that has very real consequences for a lot of people. Helping <politician I loathe> doesn't just affect me. It's a punishment for everyone.
Personally I wonder why these always involve sending money somewhere. Why not just automatically post to your socials "I skipped the gym today". Far more motivating to me than a cup of coffee.
If people are interested in using it of course, I will let people stake what they like :)