In my country general idea is that gas stations make almost no profit on gas because of amount of tax included in fuel price.
Then most of them earn they keep on being convenience stores.
Then most of them earn they keep on being convenience stores.
That arguably can't be true, because every gas station pays the same tax. That means, if you removed the tax, gas stations would still be making almost zero profit on gas (but the gas would be cheaper to customer by the amount of tax). Competitive pressure pretty much ensures that.