The possibility of building a public cash pool using blockchain technology

We are discussing with my colleagues to build a public cash pool by using blockchain.
Users pay a mount of cashes to the pool when they want to utilize some services in the
system. For example, one wants to post an advertisement to the audience. As more users
read the advertisement, the poster should pay more cashes to the pool. Vice-versa, if a user acts as a volunteer and does some “pro bono” work,he can receive some reward cashes from the pool. The hard thing is, according to our current knowledge, the public pool does not belong to the private asset of any individual with in the whole community.
Is our vision eligible in practice?