there's nothing in the protocol that blocks this kind of thing directly
even if there was, i would imagine an offline side channel would arise. at least now its pretty transparent and democratic in that basically anyone can use these bidbots. by that i mean democratic in the DPoS sense of the term: anyone who has SBD / STEEM can use them.
that being said, there are plenty of users that don't like this practice. posts can be downvoted and behavior discouraged... this post wasn't trying to come down on one side of the argument or the other, just to explain the mathematics... i use bidbots. they have value as long as trending pages work the way they do.
RE: The Exchange Rate Risk of Buying a Vote