One thing I've always wondered about these delivery/rideshare "experiences": why didn't they just sell the software on a subscription service? Like a shopify or

One thing I've always wondered about these delivery/rideshare "experiences": why didn't they just sell the software on a subscription service? Like a shopify or slack or something. Why did they also have to replace the drivers? Aside from being suspicious labor wise, it seems like a bloated way for software engineers to start a business, especially because they don't know how labor works for taxi fleets/ restaurants across the globe. Why not just make the businesses your customers instead of the end users?