I guess it might fall under a bulletproof hosting type of setup. [1] There have been many people investigating to try and figure out who owns & operates who is actually behind archive[.]today and how they're continuously able to bypass the paywalls of paid sites, continue operating with such large infrastructure with no apparent income source.

There was quite a good article posted here on HN about someone trying to figure out those questions, but I can't seem to find it.

[1] https://en.wikipedia.org/wiki/Bulletproof_hosting

Isn't it just a question of pretending to be a search bot ? Sites will allow google bot to bypass the paywall so stuff gets indexed.