I think you're confusing Uber with...umm Uber. This is exactly why Uber is evaluated at $17bil (or whatever number they're saying today) because it's ability to handle the software logistics of delivery...any delivery, regardless of whether it's a package, person or food.

It's also why we're seeing a plethora of restaurant delivery start-ups (Door Dash, Sprig, etc come to mind) as VCs race to capture the market.

Also that "rush" might be due to Uber in your mind but it isn't really a "rush".

http://en.wikipedia.org/wiki/GrubHub

GrubHub and a bunch of others were at it 5+ years before Uber existed.

2) There was a reason a large number of potential investors dropped out at around the 10bil market.