It might be profitable if the gas is a loss leader and most sales are on other items.
Well, this thread is four months old, but I’m glad there is still interest in the topic. The “loss leader” argument was used for years to justify minimum-price laws pertaining to milk sales at convenience stores. I agree that the “loss leader” strategy can be profitable in the short run for a single firm as a means of attracting customers into the store who would otherwise shop elsewhere. However, it’s hard for me to see how this could be a profit-maximizing strategy in the long-run once competing firms react by meeting the lower price to entice their lost customers back into their stores. Since gas prices are required to be posted in almost every state, it’s easy for competitors to observe what prices other stations are charging and to react accordingly.
I’m old enough to remember the gas-price “wars” of the 1950’s in which gasoline retailers engaged in ultimately self-destructive rounds of price reductions in an unsuccessful (in the long run) attempt to gain market share and sell related products and services, like oil changes, tires, and batteries.