A lot of the bigger small stores are fine for big shops, but they are more expensive than what you are probably used to paying and a lot of things just aren't there (or there's one or two varieties). It's not the end of the world shopping there, and I even managed to shop for a while at a tiny Tesco when Mr. A. was angry at Sainsbury's. Then, like now, I went to local markets like the greengrocer's, butchers, cheese store, Italian delis. But they tend to be a bit expensive as well (well, the greengrocer's is cheap).
I can get to Morrison's on the 24, but on the best of days with minimal congestion it's like 30 minutes each way. There's an area on Old Kent Rd (south of the river) that has Aldi, Lidl, Iceland, Asda, and I think a Somerfield. Problem is that you have to transfer at Elephant and Castle and cross in a subway, which isn't easy with groceries.
Whole Foods is nice if you're near there. When I've gone I've only done very limited shopping as I'd have to lug things back on the Tube. Probably a good thing because I'd break our bank account if we lived near there probably.
There's a big Tesco somewhere nearish to here, but not walking distance. I don't know if it's near a bus or tube (I am not even sure where it is because we went in a car which is a rarity and it threw off my sense of direction). It's meant to be 24 hours a day, but that doesn't include Sunday (which happens to be the only day we went there, so I didn't get to go inside).
I think most people just shop at the small stores, stop at some markets like on Strutton Ground, and go to their local corner store for most things. Some people, of course, have cars which makes this all a lot easier, but it's not something that I even want to think about.
It probably depends on the area. The first time I went to a Morrison's was about 6 months after I moved here. We were on the IOW, and I wanted to move there because of that store. I didn't know they made supermarkets like that in the UK before we went there.
