The article is almost written with two completely different tones. One is that GrubHub is offering delivery for restaurants that don't have an official delivery service. The other is that GrubHub is issuing deliveries from fake versions of restaurants or presenting restaurants as if they have an agreement with GrubHub.

I don't see why it's supposed to be illegal to pay someone to pick something up for you. Be it a bottle of Tylenol from CVS or some to go food from the local restaraunt. If the person goes there and finds out the restaraunt doesn't have takeout it's irrelevant to that.

It's obviously wrong to pose as/support fake versions of businesses or present yourself as contracted by them for delivery when you're not. Unfortunately the article has neither the wording nor information to make it clear which is actually going on. I suspect both to some degree though.