I think that's true at many coffee shops in the US (even large chains), but the discounts have varied widely. IIRC, it's 10 or 20 cents at the one I go to now, which is too small to change anyone's behavior. I think in the past it was a much better deal, though.
"IIRC, it's 10 or 20 cents at the one I go to now, which is too small to change anyone's behavior."
Curiously, I think the 10 cent tax on grocery bags has been enough to change people's behavior. I know I started to carry my own canvas grocery bag ever since I was told there was a 10 cent tax for each bag. My other motivation was simply trying to reduce waste, which I was made more conscious of by being told of the bag tax.
I think the difference might be in the bag tax being mentioned by the checkout clerk. Whenever you go to buy groceries and you want a bag, almost invariably you're asked if a 10 cent charge for the bag is ok, whereas in the case of buying coffee the price of the disposable coffee cup is not mentioned. So it's a lot easier to ignore.
If every time you got coffee you were asked if paying 10 cents for your coffee cup was ok, I think more people would choose to bring their own.
