We're talking about other humans, right? Or is this about the 30 mins pizza delivery?
Yes, escorts are on call most of the time and ready to go but let's assume that not all of them have a car nor parking is available at a client's place. Let's be reasonable when it comes to expectations.
If an escort is in DuPont Circle and gets a call from Washington Dulles it might take him 45 mins to an hour to get there by car, in rush hour even more, by Metro and bus who knows.
Let's try to walk on someone else's shoes too and again be reasonable.