Southwark do not accept brown paper bags for recycling (see link) - although if you have a compost bin you could put them into that. http://www.southwark.gov.uk/YourServices/environment/RecyclingPages/WhatCanBeRecycled.html As for Sainsburys recycling plastic bags, I think that is a bit of a red herring, as they are transported overseas for reprocessing - why not just re-use them? If you are doing a bit of shopping on the way home from work why not get into the habit of carrying a folded up plastic bag in your pocket?