It's not work experience, it's slave labour.
Sorry but pretty much anyone can work in a shop, or in a call centre, or as a cleaner or any manner of other menial **** jobs they try to push on people. You don't need experience or qualifications to do those jobs, that is why they are paid so badly.
It just feeds the poor staffing practise of the businesses involved, gives them incentive to reduce the hours of their current staff or take on less, and in the end boosts unemployment.
Put eloquently by Kevin Bridges "David Cameron says one of the aims of the scheme is to help boost peoples self esteem, how does working in pound stretcher for no wages boost your self esteem? A shop where everything is worth a pound, except you"