I'm one of those "problem" patients that *isn't*. I question it all and if I don't understand what they are doing and how it has to do with my visit I won't do it.
If they make me wait too long in the waiting room for my appointment, I complain on my way out and refuse to be billed. I shop for Doctors like I shop for auto mechanics. I'll pay for good quality and good service, everybody else gets fired.
I have my teeth cleaned every 6 months. I haven't had a cavity in my life. I tell them I'll do an xray series every other year or whenever I think I need it.
All service and goods suppliers get the same treatment. They all have to convince me that they have earned my business and charge a fair price, otherwise we part ways.
Doctors, Plumbers, Barbers, Auto Mechanics; everybody has to remember which one of us is the Customer.