This comic follows on from the Previous comic which will almost certainly provide context.
You might not wanna be famous, but when you're level 10, every organization within a mile is watching what you're doing.
Instead of a tech solution, why not a legal one? Place somewhere in the website that refusal to follow your robots.txt is agreement to pay you x amount of money for your content. Then combine that with the dummy page solution the other person brought up so you can record the IP address, then take them to court so they pay you. Has potential to bring you a really really nice chunk of money.