This is for sure the biggest challenge that eg @opencollective, @stackaid and others faces:
How to get people to accept money and (especially for #OpenCollective) how to then get them to make use of that money in a constructive way that makes it become a catalyst for an already successful project.
@tidelift kind of has their story clear here. They sign up maintainers for support to keep their packages safe and they sell those agreements packaged up with indemnification insurance to companies.