If my users want to go where I ask them not to go when they have no reason at all to go there, their problem. There are no links anywhere to those dirs, except for the robots.txt. Also, the blocks lift after a couple days. Honestly, nobody ever complained, and I'm sure it stops/hampers some attacks dead on.
What do you mean 'with bots'? We're talking about anyone at all hitting a link blocking the IP they have.
Some mobile networks have every person on the network originating traffic from the same IP. Some large institutions, universities, government departments, large companies have all their traffic coming from one IP.
This person has effectively created a feature that will perform a denial of service attack on their own website.
You see it not as problem, because user don't see you (your sites). As IPv4 are getting rare, many share the same IP. So it's really a bad practice to ban IP for a longer period.
