Yes and no...
I must confess that the gate attendant once called the cops on me because the service was so bad I refused to pay. (I paid, called for refund, which never happened, either).
After two years of dealing with lousy supershuttle, I found myself parking in the daily lot. If nothing else, the ride from daily is so short the drivers and attendants have less opportunity to be surly.
However, I had a minor restoration of faith one dawn before christmas (maybe it was the season?). I was travelling with my >75 yo mother. The driver went out of her way to load my mother's luggage and make sure she was seated safely. She lowered the bus to make it easier for her to disembark. My mother tried to tip her; she refused. I was too busy pulling my jaw off the floor to intervene.
So, the answer is yes and no....