There are more than just the American top dogs (OAI, Anthropic, SpaceX, Facebook)... especially the Chinese government with all its infinite cash resources and next to zero ethical constraints.
I don't trust the US top dogs at all, but I think the fear of discovery alone would lead them to not use "residential proxy" services. Non-US/EU entities however... who cares?
Why would they directly use a proxy service? I'd just launder the data scraping through some third party company that I could slough off if it ever turned into a news story. Not that anything would happen to them if they directly used these services anyway.