The pressure from the appropriate distance is fine. The issue with coin-op car washes is the brushes. They may have all sorts of dirt and debris in them.
Hey Tony, Are you doing any type of ceramic coating? Fabian who's doing mine told me the high alkiline detergent / wax most touch free's use wears the ceramic coating faster and the wax can inhibit the oleophobic qualities of it. I know from my own experience the touch free I use strips a wax job pretty quickly. I think they may use stronger detergent in touch free's to increase effectivness.