The OP apparently lives in either Oregon or NJ, the only two states that ban self-service gas pumps. However, that does not mean that the OP needs to sit there passively while the gas attendant does as he wants.
I live in NJ, and I take charge of the gas pumping process–either directly or indirectly.
Most of the time, I do the entire process myself in order to prevent damage to the evaporative emissions system, to prevent gas spills on the rear fender, and to prevent scratches on the paint from lackadaisical gas attendants allowing the gas cap to bounce off of the fender. Not only have I NEVER been stopped from doing it myself, but almost all of the attendants thank me for doing it myself.
In the rare instances where I can’t do the fueling myself (instances where the attendant must first insert his card in order to activate the pump), I make sure that I am standing next to the pump when it clicks off. At that point, I simply say, “That enough…NO MORE!”, or “Bastante…NO MAS”. This yields the desired result.
All the OP has to do is to get out of the driver’s seat and stop passively allowing gas attendants to do as they wish. It is YOUR car, you are the paying customer, and YOU should be controlling what goes on with your car.