I would suggest that if they can offer that as a discount, it may well reflect what cut they are taking from the restaurants sales. So not a 'loss', merely a failure to reap a profit on that sale.

I would further suggest that the sale price of the product is increased by a said amount.

Or we could look it up... (its 30%) To do this I asked Bing "how much does it cost restaurants on uber eats"

https://www.ridester.com/uber-eats-fees/#:~:text=Uber%20Eats....

https://entrecourier.com/delivery/gig-delivery-platforms/ube...