I like the gas container answer. Or (strange as it may sound), if you are already full when you get there, how about finding the worst looking vehicle at the pump (maybe one with several kids who seem to be of lesser economic status) and "paying it forward" by offering to buy them $5 worth of gas? For some people, that might mean the difference of feeding the kids that night or not. Just a thought...
My husband bought super cheap gas and shortly thereafter, his SERVICE ENGINE NOW light flashed on. He had to have that gas emptied from his tank and the whole system flushed, cost him $268.00. He went to the station where he purchased the gas with the invoice from the service station, which stated exactly why he needed that done. The gas station reimbursed my husband for the entire cost of the bill!
Yes, we are still trying to pick up our jaws from the floor! There ARE honest people in business out there!
Might $3 be enough with the other two being added to the shop fee?