I have had to wait at a Supercharger also. So far it has been twice, both in Southern California when visiting my daughter and grandkids. One at the Westfield Mall charger near Culver City and once in Orange County after visiting Steve Williams (of WBF). Otherwise, I could immediately find a spot. Will have had my Tesla for seven years in February. Normally they are next to Malls or restaurants, so we go shopping or eat while the car charges up. Of course, when we are driving locally, we just fill up with electrons at night at home - plug in and go inside. The timer is set for midnight the time for the lowest cost electricity. In equivalent cost, we get about 100 miles per gallon.
Larry