Like many other phpBB boards, my board is plagued with spammers and bots. I am currently in the process of trying to update my phpBB board to the current version and implement a few anti-spammer measures.
For now, when a spammer is identified, the user is banned. However, this clutters up my banlist severely, and I prefer to use it to keep track of real users who have been banned for bad behavior, but that is difficult to do when most banned users are bots. I have been reticent to delete the bots, though I realize I'm not really sure why. I heard once from an administrator of another type of board (vB, I think) that deleting users can create holes in the database and cause problems. I don't know what this means but I wonder if it matters in the case of users whose posts and whose topics will not be missed.
How do other administrators handle the spammers and bots? Just delete them and get them out of the memberlist - or is there any reason not to?