It's the trend that more and more stores accept them. All the stores in my area do (with the exception of Aldi). Maybe it's just your local store; as Missy suggested print out the coupon policy and ask to speak to a manager.
I was going to suggest what Missy posted. I have a printout of their policy that states they do take internet coupons so you can just pull that out and show them. But I've never had one turn them down.
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A woman is like a teabag. You never know how strong she is until she gets into hot water.-Eleanor Roosevelt
I tried to use them at Walgreens today. The cashier said they don't take them. There was a huge line behind me so i sucked it up and bought the products. I think I'm going to take them back because they were totally overpriced with not being able to use my coupons =(