Earlier this week Sainsbury's published some great sales results but chief executive Justin King was quick to add on a warning that "what is going to happen in 2010 is the reality that people feared in 2009".

This is consistent with his comments we previously noted in September. What we don't know is why he is talking down the future – because he is planning for lower sales or because it will make his company's performance look better?

On the balance of probabilities, it is likely that shoppers will have less money to spend and how they spend it will be important for local shops. For many shoppers, the problem with the big weekly shop is that they buy too much stuff and throw away food.

The obvious solution to this is for the shopper to plan ahead and do a better shopping list and stick to it. The alternative is the local convenience store and top up shopping, which requires less planning by the shopper.

If you believe you have a good opportunity to pick up sales from top up shopping, have a look at your store and your local marketing and check if you are encouraging local people to think that instead of sitting down and doing a list, they can rely on your shop when they run out of stuff.

US retail expert Bob Phibbs comments on the same phenomenon that "to those who want them, the customers are out there … Go get ‘em!"