You brought up an interesting point which proves that bidbots owners are solely looking for profit (excluding those who delegated their own SP to their own bidbots). To be straightforward, I am sure that bot owners work so hard to keep up the quality but simply as a human, they cannot do it without poisoning the environment, the complain on the trending page is the best example.
People are rarely coming on trending without using bots and that definitely shows the current state of steemit.
RE: Introducing Instant Voting Bot - @bdvoter with guaranteed profit for Buyer and Delegator