The eventual result is that Uber can operate more efficiently than competitors that only do rides or food, allowing them to compete better in both markets.
(I used to work at Uber)
ubereats is a flanking product, meant to protect the core business. strategically, uber really only has market power on the supply side, and ubereats is primarily about protecting that advantage and less about being a standalone business (although i'm sure they'd be thrilled if it succeeded as a standalone business).
i'd be surprised if ubereats went away any time soon. at least, not without something else replacing it.
I'd say that Uber has zero moat in it's core business, anyone with a little bit of cash can roll out a competitive alternative in any city onces Uber raises prices.
But with Uber eats, a competitor has to also roll out meal delivery in order to be equally profitable and thus competitive.
Still not a huge moat, but a little bit harder to beat.
Uber has a huge most that Eats adds almost nothing to. Every day millions of people reach into their pockets to request a ride using the Uber app. Competing with Uber means a) recruit large numbers of drivers so your app has rides to offer. b) convincing large numbers of people to download your app. c) convincing them to make your app their primary ride share choice.
Even tackling a small city would be horrendously expensive. If it truly was easy Uber would be getting eaten alive by numerous small startups in every major city they operate in.
I can't imagine that a food delivery service could be competitive using drivers rated for safe person delivery.
Is the driver fleet for Uber eats even the same as the minicab fleet or is it really just another business?