[malandrew]

... but still allow me to delete it if I prefer using another food ordering app instead like GrubHub.

The only apps that should not be deletable are core apps like settings and the app store.

Even those should be deletable if it asks you to designate another app on your phone as the replacement for that core service. That replacement app should be API compatible with the data store of the phone itself.

I should be able to replace Apple Maps with Google Maps. Camera with any number of other Camera apps. Photos with any other local photo browsing app. Calendar with something like Fantastical. Weather with something like Yahoo Weather. etc. etc.