Why scare other folks who may think it is smoke from a cigarette? If you can't wait the three or four minutes then you have issues. Anyway, when pumping gas, you ought to pay full attention to that task and leave your vapes in the car.
That would concern me more than anything, especially at a gas station that's always busy. Other customers being concerned & possibly getting scared. That would just be more fuel to the anti-vaping community (or those who doesn't know what vaping is), showing disrespect for others & causing paranoia. I still get strange looks just when vaping in a parking lot or sidewalk, some from those who happen to be smoking.
Can one imagine the stares at a gas pump?
I'll admit, I've vaped while pumping gas, like when cleaning the windshield, however I was the only customer there. When others are around, I can wait until I get back in the car, or at least away from the pumps. What I do, is get a few good draws before I get out of the car. That carries me over for the 10 minutes or less that I'm going to be there.
Cat