Sharing idea's are pretty useless in general, if you're not excited enough to work on your own idea, why would someone else be excited to work on it?

I'm curious if people posting things they NEED would be more functional, along with a bounty. Other people who also want it can contribute to the bounty. Anyone can work on the idea's and the bounty is awarded to whoever solves it first/best. (I think you would need some sort of oversight to make sure the bounty is awarded to the rightful solution).

"$1,500 - An API that lets me send send snail mail by posting a PDF and address to an endpoint"

Maybe it slowly gets up to $4,000 with 15 other people contributing to the bounty. That's finally high enough that someone solves it, posts it, collects the bounty, and already has 16 customers.