Contractual obligations carry teeth. Scraping the internet is relatively risk-free.
Good luck proving your data was laundered and included in a training run
Lucky for us Apple is already alleging something to this effect in their trade secret lawsuit, so you know they'll make sure discovery turns this up if it exists.
Anthropic happily paid billions to settle a lawsuit for pirating books. It's a trivial cost of doing business. If you're lucky you'll get a pittance after the fact by suing them, but a contract doesn't prevent them from doing the thing you don't want them to do and that they are obviously going to do given their past behaviour.