>the law explicitly allows scraping and crawling.

Nepenthes also allows scraping and crawling, for as long as you like.

this is a very US-ian view of the world

my site is not in the US, I am not a US citizen. US law does not apply to me.

under UK law: robots.txt is an access control mechanism (weak or otherwise)

knowingly bypassing it is likely a criminal offence under the Computer Misuse Act

good luck suing me because you got stuck when you smashed my window and climbed through it