Bots, beware!

Our site gets dozens of bot registrations on a daily basis. I believe every site with membership does. It is so pointless (and yet so easy to achieve, so "we do it because we can"), that its depressing:

[11:55:18 AM] alexey.yurchenko: I wonder, what amount of data in the databases of the world consists of bot registrations... How many billions of rows are being scanned or indexed daily... Kilowatts (or megawatts?) of electricity wasted...
[11:56:34 AM] alexey.yurchenko: But most importantly, does this fraction grow with time? And is it related to entropy laws?
[11:59:00 AM] seppo_jaakola: websites should push their entries in The Universal Index, maintained by UN, and TUI access would be leased for commercial purposes
[12:00:09 PM] alexey.yurchenko: and it all should be obviously run on Galera - for faster global distirbution and access...
[12:00:40 PM] seppo_jaakola: that goes without saying
[12:01:19 PM] seppo_jaakola: after this, website crawling would be considered as criminal action

— the "Final Solution". ...sigh...