There are immediate disincentives to trolling, it's not financially rewarded and people will be most likely downvoted until you can no longer see their posts. That's why there are so few trolls.

As for the allocation of the reward pool, of course groups will form and certain users will milk those rewards daily, or multiple times daily. If people can band into groups this will always be an issue.

It's certainly worth it to invest your time here, there are lots of layers though. Overall it's incredibly positive, with probably one of the best 'family like' groups on the internet I've ever come across. Maybe I'm a little too analytical but I think we always need to remain vigilant, certainly people have tried to take advantage of the generosity of people on this platform in the past.