You know what? - It could be literally anything that makes these posts go big. One of the things, which is a fact, is the following they have. Follow-trails, followers or bots. It doesn't really matter in the long run, as it's still their followers.
What I personally think is a bit sad, is the fact that some people spend several hours writing a super long post.. And they get $0,01 for it.. Meanwhile others are writing a few sentences and get rewarded with hundreds of dollars. That's unfair, but it's also life.