I’m on mobile so I can’t find the article but basically each lease is held by a barely capitalized independent entity. If WeWork wanted to close down a specific site they could merely shut down that specific entity without incurring obligations/fines/penalties to the entity of WeWork.
Normal these sorts of things aren’t allowed and building owners won’t sign up for that but somehow WeWork was able to bamboozle a bunch of developers into agreeing to that.