I tried something like this with a friend of mine in 10th grade.
I was making $2 a day working at a lunch cart. I ended up giving him $2 a day for a week or two, as a failed incentive to do my homework.
The conversation went something like:
After a little while it felt pointless, because I was giving away all my money, and not doing my homework. It still seems like a good thing to try though.
Related to the recurring topic of akrasia and anticipated near-mode losses, here's an article about "Gym-Pact," an arrangement whereby people precommit to pay penalty fees if they don't stick to their planned workout schedules.
In other words, they aren't charging customers money in exchange for a service, nor for violating an agreement associated with a service... rather, they are charging money as a service.
Had I encountered this in fiction, I would have considered it satire.
(I'm being somewhat glib here, admittedly: in this "experimental" phase, they are giving people free gym memberships as part of the deal, and using the penalty fees to pay for the memberships. But that doesn't sound like the ultimate business model.)