A huge fraction of cars driven by Uber drivers are made by Toyota. More often than not, you'll get picked up by a Prius, Corolla, or Camry. So to some extent, this is about maintaining market share.
Toyota has an existing partnership with Uber for leases to drivers.
If Uber's thesis - that app-hailing will supplant car ownership - is correct, then car manufacturers have an incentive to either create their own hailing networks or partner with existing ones.
