I trust math.
Assuming 20 mpg, you might save $2.50 with all that time an effort. Standardized depreciation is almost double that and a 37 gallon tank vehicle probably isn't standard.
Maybe it used to work out with a wider spread and cheaper gas. Or a modified Prius.
Just to clarify...before this proceeds, you're going to continue to argue this point with me...when you're not me? You're going to proceed to tell me that it wasn't worth my time to go across the Delaware and fill up my tank? To start with, it isn't the price of gas that matters (aside from the fuel used traveling to the station). It's the price difference.
It worked out to about $6 saved each time, and it cost me very little of my time, because I'd do so either during or after work. That was a couple happy hour beers at Barley Creek. It works.