[curiouscavalier]

Many do go out of business, and many substantially undercut others. This is particularly true for the diesel market, where OTR truck operators are more price sensitive. Most stations are buying gas around similar prices at the terminal, but their overhead to provide the station can vary wildly between large chains and small, family owned stations.

“Skimmers” (drastically lower-priced diesel stations) are a real threat to larger chain stations. They don’t put them out of business entirely for a number of reasons, but one is because gas stations ultimately sell more than gas/diesel (e.g. a clean bathroom is often worth a few extra cents per gallon for me, but there’s a lot more than that too). Also any given station can’t sell an infinite amount of fuel. Beyond tank capacity, wait times are a real impact on sales volume, and so if a station offers a price too low (even if still profitable), it is just leaving money on the table.

So not to say collusion doesn’t happen, but one can also arrive at similar pricing with a commodity like gas without it. Especially since fuel margins are typically low.