What does "one coupon per purchase" really mean?

I've been frustrated lately with the 'misunderstanding' of what "one coupon per purchase" really means. SO I set out to find an explanation that I could pass on to everyone. I found this at CouponMom.com and thought it was pretty clear.

Question:  From Sassy:  "I recently have found that some retailers are saying that you can only use one coupon per order when the coupon says 'one coupon per purchase.'  It would be good to have a list of the most common restrictions and what they mean according to the manufacturer so we have ammunition to support the intent of this policy.  I have never run into trouble in all my years os using coupons (30 years) until just recently, trying to buy 8 bags of cat treats with 8 coupons, which read one coupon per purchase, which I understand to mean one coupon per item I purchase."

Coupon Mom Answers:  Although it is always up to the retailer to decide how they will accept coupons, there are standard terms and restrictions on grocery coupons that manufacturers use to clarify their intent for coupon redemption.  However, sometimes a cashier or store manager will interpret the coupon terms differently than the manufacturers intended for them to be interpreted.  I agree with you that if shoppers understand what coupon terms mean, and they are able to politely and logically explain the intent of the term, it is likely that the store personnel will agree to accept your coupon.

Examples of common coupon terms and their general meanings:

• "One coupon per purchase":  This means that shoppers can use one coupon per item, with the item considered to be the purchase.  For example, if a shopper had 10 identical jars of spaghetti sauce and 10 grocery coupons for that spaghetti sauce, she could use all 10 coupons for her order, which is literally 10 purchases.  She could not use 2 manufacturers coupons on the same item if she was only buying one jar of spaghetti sauce because that would be more than "one coupon per purchase."
  

• "One coupon per order":  This means that the shopper can only use that specific coupon once per order.  If a shopper had more than one coupon, they could use one coupon per store visit, which would be one coupon per order.
  
  
• "One coupon per household":  This is the most restrictive coupon term.  Some coupons are so generous that stores will limit their liability by making sure shoppers do not make multiple trips to the store to use several coupons. 

The most common coupon restriction is "one coupon per purchase," and when store personnel interpret this term as "one coupon per order" it can create frustration for honest coupon users.  Therefore, familiarize yourself with these three restrictions so that you can calmly and politely explain what they each mean.  Then you will easily be able to use multiple coupons when buying multiple identical items to save the most.

However, if you still encounter a store that refuses to accept more than one identical coupon per order, I would suggest that you write a polite letter or email to the store's corporate headquarters to express your concern about this policy.