GrubHub tends to lean more on merchant costs (like commission) than consumer fees. This is why lately you may have seen (a) scary looking news articles about GrubHub taking half of a restaurants income, and (b) cities talking about emergency orders to limit commissions.

But either way, the economics are roughly the same: getting food made and delivered to your door is really really expensive. It just comes down to how that gets sliced between restaurant, consumer, and driver.