How about schemes that are less obvious, such as communities receiving benefactor rewards from posters in return for votes such as olio de balena or membership schemes that return upvotes to its members' regardless of post quality, such as SSG.
I would love to see more action taken against all of them, but my personal power and time are limited. I also had issues in the past being blackmailed with full fledged campaigns to remove my witness votes, so I'm reluctant to act at all.
Do other incentives such as HBD cashback schemes and large votes for using distriator count as buying votes? Or those rewards given for using the product rather than just supporting it.
IMO, distriator is an edge case. @starkerz is trying to boost HBD adoption, so there's at least some genuine intent to spread Hive. It's not scalable long term, so we'll have to see what comes out of it, but I wouldn't spend resources on throwing stones their way as long as it doesn't get too much. Maybe someone should do some math how much is spent and who gets the rewards in the end, but I'm not that guy.
As for HSBI, is it really that much different than auto voting from a human?
Yes, because you paid them for the votes.
Also, the project is holding several hundred thousand HP as their own by now, and all they had to do for it was set up a voting bot (I know they do more to mitigate the worst abuse, but it essentially boils down to that). The users who paid them do not have this power any more, and the votes will not go to people not involved in the scheme.
It appears there needs to be distinct definitions drawn up on what is acceptable and then absolute consistency in application without prejudice regardless of the account's size.
There can't be absolute consistency, as everyone's resources are limited and most don't even care. Also the schemes all differ in several aspects and have to be investigated and judged individually, as I laid out with distriator.
I will focus on cryptocompany for now, because that's the most blatant one we've seen so far. How it goes from here depends on the reaction of them, all the other schemes, and what further investigations uncover.