Among the self-congratulation it should be remembered that they first used to sell the paper ones with string handles for a few old pence. It then rapidly became obvious that if free bags were provided customers would have no problems carrying their goods out regardless how much they purchased. Secondly all that went from the trolley through the checkout, went into a store plastic bag to be carried out.

The new situation is that customers take, round the store, in their trolleys a multitude of different shopping bags. No longer can all the items be easily seen. It must now be a major unwanted security problem, making sure that items are not 'accidentally' thrown into the shopping bags sitting in the trolley and unfortunately missing the checkout scanner.

Many shopping outlets do not allow customers' own shopping bags into their store area. How long before the supermarkets adopt this procedure?

Paul Thompson, Scarcroft, Leeds