While I've never heard of either of these companies (maybe because I'm american?), it seems like wider selection is better than "up-scale" food. Delivery on top

While I've never heard of either of these companies (maybe because I'm american?), it seems like wider selection is better than "up-scale" food. Delivery on top of expensive food is a once a month prospect; cheap food delivered cheaply is a daily prospect. To put this another way, I've spent the vast majority of money on uber on uner x, not uber black cars. Low margins are harder to pull off but are much more stable and easier to scale. Why don't they just offer all restaurants, sort of like postmates did (does?).