Understood, but for many of us, large airport, small airport, in between airport, there is no gas around for less than four bucks a gallon.
I wish it weren't so, but going to airnav and plugging in my home airport, KGAI, gives me a price of $3.54 to $6.77. Ah, but wait, you'll say. There's one airport with a price of less than four bucks a gallon.
Uh huh. It's KVKX, one of the DC3 and you also have to be a member of the fuel club and pay $25 a month to get that price.
For many of us, the $4.00 threshold you're using is just not possible.