Hi Mary T, I absolutely agree with you.
It's so wasteful to take a carrier for one or two items, or to just use carriers and throw them away. We always re-use any carriers we take, but whenever we remember, we take out "proper" bags-shoppers, foldaways etc., that we can use over and over again.
When i worked in a shop, I used to ask customers if they were sure they wanted a bag, and I got so many filthy looks and "Are you stupid?" answers!
If I forgot a bundle of bags, I would be happy to pay for carriers-it would serve as a reminder for next time!! x