you make some pennies of profit from newspapers, chocolate bars etc biggest profits are from cigarettes, birthday - christmas cards, lighters, the sweets in the jars. if you can keep high foot traffic you can make a good profit, my old boss once had 6k through his til in one day but that's with it ran correctly, otherwise you can scrape a minimum wage equivalent and keep costs down by not hiring others to work for you.  i worked at one for 10 years.
United Kingdom