As a couponer for almost five years, I've been to some very coupon friendly and not so coupon friendly stores. CVS, Wal-Mart, Rite-Aid, Dollar General, Kroger and Walgreens are a few that are very coupon friendly. Every now and then I may run into a problem but its not of something they couldn't fix. Family Dollar, Food City and Meijer are a few stores that have done nothing but give me trouble. No matter what I do in these stores, they'd always find an excuse as to why they couldn't take my coupons. I have given corporates calls just to inform them on how there stores need to get with the program. I don't like to complain but they need to know there policies and let those that want to use the policy should be allowed if utilizing correctly.
In the south we have Publix supermarkets, and they are coupon friendly and let you stack manufacturer coupons with store coupons. But sometimes at Walmart, they don't know the coupon policy so I have to bring a printed copy of it. I think stores that accept coupons should train all their employees about coupons instead of having them be rude to customers with coupons.
I know that CVS will never take a printed coupon and will only take a manufactures one or one that is from their store directly. Wal-Mart accepts printed coupons and manufactures coupons alike, but I don't think you can combine them. Acme takes coupons, but again, nothing printed only ones from manufactures.
That's very odd that Walmart employees wouldn't know the coupon policy. :S I would think that coupons are fairly common for Walmart shoppers and it's not a rare exception. Are you trying to use unusual coupons or are they pretty straightforward ones and they still don't know how to use them?