It's similar in some ways but overall a very different business model which doesn't work out nearly as efficiently.

When you're delivering pizza, you generally just work out of one location. You have a relationship with the business you're working at which includes an area set aside for deliveries where drivers can both plan the orders into batches of ones that work well together, considering when they'll come out of the oven, their destinations, and what the other drivers are doing. When it's busy, drivers can go in, look over all the current orders (ready or not), and take deliveries to their cars without needing to interact with employees at all. In some locations, they might also be considered kitchen staff and can also do things like pick orders or cook items that aren't yet ready, allowing them to both provide value to the business (further justifying a wage) and get deliveries out the door sooner.

A lot of that isn't the case for delivery services. The food pickup can be anywhere, so you can't just go back to the restaurant and wait, and the pickups need to be optimized just like the dropoffs (if the service even allows you to batch deliveries together). You don't have that relationship with the business; you're basically just another customer, so no going to the back to see what's up or helping the employees when they are swamped.

I've done pizza delivery in the past. I didn't mind it. I don't think I would like delivering for one of these apps, it sounds like a giant pain in the ass.

Pizza delivery is generally handled by each individual restaurant with some dedicated employees, so it's a pretty different model than something like Uber Eats. Pizza is also fast, cheap, and simple, so that helps to drive down costs. It's also generally a complete meal for at least two people, if not a whole group, and so the delivery cost gets split across more people.

I get the comparison, but I don't think they're really as analogous as they seem. One is a pizza place hiring a delivery person or two to drive some pizza around; the other is a large tech company settled with debt and inventor obligations paying very expensive engineers to manage incredibly complicated logistics networks and deal with tens of thousands of distinct parties.

This is really kinda my point. Why is pizza delivery so much cheaper? Because it doesn't have to deal with all these extra costs that a massive delivery network like Uber inherently has to manage. I imagine we'll eventually hit some kind of equilibrium where a lot of restaurants that can manage it have their own in-house delivery people, while the large networks will have to dramatically downsize or die.

That's precisely my point. It's ultimately a shitty business idea, and will probably eventually fail.

I don't really understand what you mean by being on the hook for it. Investors will ultimately lose quite a lot of money, workers will lose their jobs, and customers will endure the horror of walking or driving a bit to grab food.