Amazon has its own Uber, own fulfillment service down to monitoring tools that are built in house. So, not sure if it's a change in their "buy vs build" strategy or there's a more business play here to gain traction in the global markets?
You got to give something in return. In this case I think both parties have something that the other side wants so why not?
Though... that was also because their main handheld vendor (Zebra) bought their own warehouse robotics company, so a bit of a signal to Zebra that they don't play well when their partners become competitors.
https://renovotec.com/press/amazon-2nd-largest-shareholder-p... https://www.communicationstoday.co.in/koreas-point-mobile-ex...
Anyway: Amazon Flex drivers actually did handle delivery for Amazon Restaurants, which was a direct competitor to Uber Eats, DoorDash, GrubHub, Caviar, etc.