Post changing: Wow, that's shady. Yeah, with the 7 day payout it can be awkward if something you vote on gets turned into spam. Thankfully, everything is on the blockchain so it can clearly be shown what happened when.

As to your beef with sneak, maybe hit him up on chat first? Vote buying is generally something that is frowned upon here, but there are many forms of it, some better than others. If someone does a "vote up this post and I'll..." then that usually gets a downvote. I'm not familiar with what you're doing, but if the main developer from Steemit, inc doesn't like it, you may want to ask around in chat to figure out why.