Fair enough but I wonder how much of that has to do with simply being asked? Being given a bag was standard, as normal as expecting the store to be heated. An invisible service.

Now, you don't get given a bag for your Sandwich & Water at lunch, and you don't get a free bag with your McDonalds meal to name just a couple of services.

1p or 5p wouldn't make much of a difference? A Family paying 100 pound a week on shopping at a super market, can easily just spend 100.35 on 7 bags and won't bat an eye lid.

If that was 107.00 that would make a real difference and I bet the decrease would be much greater.