Does this strategy still work? The logic behind it is that the air is cool in the morning and the gasoline affected by that change in temperature will be somewhat denser. So when you buy gas in the morning, you'll be getting more of it than someone who'll refill their tank in the afternoon. I don't entirely buy that theory. Thoughts?
Yes, it is an interesting theory @Denis Hard and one that I will take note of because I usually fuel up when needed in the morning hours around 8:00 AM EST. But how could one really notice the difference I wonder because you can only gauge the amount of fuel by the fuel tank marker. I will say that sometimes I am surprised on days when I venture out and about after fueling in the AM that the marker hasn't move much after I'm parked and I may have driven around for 4 hours covering a lot of territory in the city. Good OP.
It's certainly enough to affect the price by a few cents/gallon. What is important is in countries where fuel is expensive, people will often drive to a fuels station, spend 50p on fuel to get there, and only fill up £10, 5% of the entire cost! So generally unless you are already passing, you should fill up as much as possible.
You are totally right in being skeptical about this theory - especially as its actually a myth and in fact one that has been debunked many times over. Simply because - even allowing for the fact that gasoline does expand and contract a " little " depending on its temperature - as gas stations store their gasoline in underground tanks - where the temperature not only remains relatively constant but the variation in temperature is way less than in the air above ground - and therefore - the temperature of the gasoline coming out of the fuel pump into your gas tank - is unlikely to vary, if at all, during any 24-hour period - you'll get the same amount of gas whatever time of day you choose to refuel.