Way back in January I suggested posts using paid votes should be detected by the UI, removed from 'trending' or 'hot', then placed in the 'promoted' tab. Paid votes basically means paid programming, converting the content into a form of advertising regardless of what's inside.
Ford will buy a television time slot at noon on a Sunday to offer the world an advertisement disguised as a show about people testing cars. One half hour of positives reviews. If the mock television show didn't come with a warning at the start about how you, the viewer, are about to watch paid programming, Ford could get sued for false advertising. So I've also suggested posts converted to promotions/advertisements be labelled accordingly. You can scroll through trending on Youtube, see organically popular content, then they slip and ad in but it's no secret that particular link is an ad because it's labelled.
Then people wouldn't have to pay bots and do anti-social activities.
They don't have to. They were misled by unmarked ads on a trending page. "It's hard to get noticed," they said, creating the 'problem', then they offered the supposed 'solution' for a fee. That's the oldest trick in the book to get someone to buy an idea. The ads looked like friendly bloggers who believed in the platform and want to help. McDonalds looks like a friendly place to eat when they advertise as well.
This current situation is mainly a UI issue, I agree. People are exploiting the design.