Boards
I find it surprising that most independent or small chain shops can survive.
Consider your local newsagent. Do you often spend more than a few quid in there at a time? Yet they can somehow afford all their costs (rent, utility bills, whatever licences you need, etc.) and to pay for at least two people at a time to work there 7 days a week and leave enough to pay for living expenses.
Even when you look at something like Hummingbird bakery: their shops are all in the most expensive parts of town yet apparently there are enough fat bastards buying cakes at £2-£3 a time to pay for the whole shop to keep running.