Charity Shops are mainly a British phenomena. They benefit from tax concessions. They are exempt from corporation tax, pay no V.A.T. on donated goods, and get 80% business rates relief. In some areas local authorities let them off the remaining 20% (meaning no business rates).
Abingdon Town Centre has 9 charity shops:

Action for Peoples in Conflict
British Heart Foundation
British Red Cross
Cancer Research UK
Helen and Douglas House
Oxfam
Scope
Sue Ryder Care

The shops rely on volunteer staff for whom this is a chance to do something worthwhile and to meet people. I would have thought that we had reached saturation point with 8 shops, but the most recent arrival, Helen and Douglas House, is one of the best charity shops I’ve seen anywhere. nThese hospices for young people were set up by Sister Francis and are a well loved local charity.