Last week, after spending 30 minutes placing one order in Uber Eats, I finally hit the last confirm and it told me the restaurant was no longer taking orders that night. I called the restaurant and they said they couldn't help: they only take orders over Uber Eats and they can't control UE's system.

Yes, they absolutely could help. They could take an order over the phone. They could choose a subcontractor who delivered good service to the restaurant's customers. The restaurant is 100% responsible.

If I used a subcontractor for a client, not in a million years would I tell the client, 'the subcontractor's failure isn't my problem; I can't control them'. I would look like a joke, entirely unreliable and clueless.