Question: do these bots not respect robots.txt?
I haven't added these scrapers to my robots.txt on the sites I work on yet because I haven't seen any problems. I would run something like this on my own websites, but I can't see selling my clients on running this on their websites.
The websites I run generally have a honeypot page which is linked in the headers and disallowed to everyone in the robots.txt, and if an IP visits that page, they get added to a blocklist which simply drops their connections without response for 24 hours.
Even something like a special URL that auto-bans you can be abused by pranksters. Simply embedding an <img> tag that fetches the offending URL could trigger it, as well as tricking people into clicking a link.
> Question: do these bots not respect robots.txt?
No they don't, because there is no potential legal liability for not respecting that file in most countries.
You haven't seen any problems because you created a solution to the problem!
> The websites I run generally have a honeypot page which is linked in the headers and disallowed to everyone in the robots.txt, and if an IP visits that page, they get added to a blocklist which simply drops their connections without response for 24 hours.
I love this idea!