I agree that humans will do what humans can do and bots will do what bots can do. Laws are murky and I don't wish to donate to lawyers. I believe engineering solutions when possible is the answer.

Using simple conditional tests in haproxy, I stop most of the bots from crawling anything more than my root page, robots.txt and humans.txt. Anything else gets silently dropped and the bots will retry for a while then go away. I don't see anything in the logs beyond the root page and robots/humans.txt any more.