It boggles my mind that you simply "apologized" to the other van passengers.
Why didn't you contact (by phone if nec.) Supershuttle to cancel.
The driver waited because he probably thought you would be right down. 1 minute turned into 30 minutes plus.
If I had been another passenger, I would have been livid.
Supershuttle should bill the tardy passenger $100 for each other passenger and give to them. Sorry. Just my opinion.