You're welcome to deduce trustworthiness from anything you like. But people have been asking "Cui bono?" for 2000 years, so you're unlikely to change many minds there.

When I worked as a consultant, I never took vendor kickbacks like these. At the very best, they created the appearance that I was working for somebody other than my clients, so that I'd have to work a lot harder to maintain client trust. The worst case was that they'd distort my thinking without me noticing, meaning that my clients shouldn't trust me.

I think it's the same deal for writers. The whole point of incentive systems is to distort behavior. It's not unreasonable that people assume that they work.