Anybody who's towed anything has a story about blocked pumps. I find I'd rather pay a few more cents a gallon than get stuck behind the inconsiderate SOB's. And since the F150 has almost double the fuel capacity as my Envoy I don't stop as often.
We had the HTT on the Mass Pike and stopped for fuel. Both pumps were open but I stopped at the first one - no use blocking the whole island. I waved the guy behind me that the front pump was open. He actually came back and thanked me for not blocking both pumps.