I'm unashamedly in favour of Sainsbury's simply because it offers things that no-one else on the parade does. It doesn't take my money away from other shops on the parade - it takes money that I used to spend in other supermarkets in the centre of London after work or at the weekend.
However, I would also like to see local independent shops prosper. To do that, I think they need to diversify and offer something different. I'm no Mary Portas, but if I owned a mini-mart I would be thinking along the lines of perhaps offering a range of good quality and authentic Indian/Thai/Chinese foods or tying up with local independent suppliers - say, Peter James butchers or Mr. Lawrence wines - to offer more interesting and better quality products than Sainsbury's can. I would also make a plea to local mini-mart shop owners to ditch the huge, gaudy plastic signs and tatty window posters - look at Hills and Parkes or Neroli for how to make your shop look attractive and inviting!