Do charity shops benefit the local economy?

Are charity shops a good thing for the local economy?

The Chamber of Commerce doesn't think they're good for Honiton:
Futures Forum: "We don’t want a main shopping area of charity shops and coffee chains."

And there's a lot of resentment about them in Plymouth:
Are charity shops killing Plymouth city centre? | Plymouth Herald

Charity shops enjoy huge tax breaks:
Futures Forum: Corporation tax, small towns and small businesses >>> giving SMEs the same 'level playing field' as multinationals

And a recent study shows them to be pretty inefficient :
Curb the number of inefficient charity shops that clog up our high streets, say charity campaigners - Telegraph

Here's a debate on the issue in Sidmouth from a couple of years ago:
Futures Forum: Sidmouth: a town of charity shops and coffee shops?

And here's the front page piece from the latest Herald - which gives an interesting take on what charity shops are doing for the economy of Sidmouth:

‘Ingenuity’ of Sidmouth charity shop coach tours celebrated - Breaking news & sport in Sidmouth | Sidmouth Herald
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