Coupon Policies - What's the Deal?

Warning - Rant coming on
Okay, I love coupon shopping, it is fun, saves a ton of money, and there is a huge feeling of satisifaction when you get a really good deal. If everything works the way it's supposed to. But what's the deal? It seems like the most of the cashiers don't know their stores coupon policies, half the time the stores don't know their policies even! The worst offenders have got to be Walgreens and Fred Meyers. Their rules literally change depending on who the cashier of the day is. At least with Walgreens they have a published policy though, so most of the time it can be straightened out pretty easily. I can't even locate a policy for Fred Meyers, and everytime I go in the rules are different. I guess it's good that I don't need to shop there a lot, but is it that hard to train your cashiers in your own store's policy? Come on people!