Gas stations in Germany are not making much money with the gas sales themselves. The main companies behind them, like Shell, BP and co. do but the stations are usually franchised. They mostly make their money by doubling as a shop that is open atearly and late hours and on sundays, as many German muncipalities ban other shops from being open then.

So people often also buy something, or particularly in the morning get some breakfast and a coffee. Perfect time to charge the car a bit.