I am in the process of moving to Honor Oak Park from somewhere not dissimilar in South West London. When a Sainsburys Local opened here there was the same scare mongering that all the other shops would close down. Years later all the convenience stores, newsagents, off licences etc are still open. The prices of some items in a Sainsburys Local (ie veg) are a lot higher than other shops so if the existing shops could offer products at a lower price I am sure they will continue to do business. Also some people like a more personal shop. I personally like the little sainsburys because it's easy to find stuff and they sell scotch eggs.