The bots definitely subtract value from the community. This is a very big problem for steemit and hopefully they are thinking of a plan to address it.
The owners will continue to run them as long as there is profit. Maybe there are ways to alter the system so it requires the user to solve a captcha to limit what bots can earn.
There is no way to control it. As soon as "someone" has the power to limit or remove money from accounts the whole house of cards falls as faith in the algorithms will be broken