The reason they keep making more is because they can expect a tempting duration of time between the time someone bothers to report them and the time that they actually get banned and have to make a new account. Consequences are not sufficient to be a deterrant. If they were caught and banned very quickly and reliably it would cease to be worth their investment of time and they'd move on to other more lucrative activities.
I had to laugh at the idea that people who deliberately act like botters to troll bot farmers 1) exist and 2) deserve any consideration if they did exist. Acting like a botter to troll people would be griefing, which is bannable, sooooo...no pity, banhammer away.