You mean people don't like paying 50-100% more for food? And having it be subpar because of delivery times. I'm shocked. When they had a lot of deals going on it wasn't so bad, but that's mostly over.
About the only time I "use" them is when restaurants basically use them as their online menu.
One of the restaurants by me let's you use either GrubHub or chownow when you order online. The prices are like 20% different between the two. It's been a while so I forget which one is the more expensive.