Options in major cities are much more limiting. The nice places like that are absurdly expensive. Rover helps make it more affordable to board your pup for longer trips.
My building in Miami has a 24 hour dog walker that you can call or text, and if you've got an apple device, you can even facetime with your dog, and it's part of my Condo Fees. Because of that, I really have no need for Wag or Rover.