@thejynxed: No need for insults. Needing to throw one on the first sentence is usually an indication that you lack the means to back up your claims normally. This restaurant owner doesn't know what the intent of the grocery store is - for all she knows, they love her business because many local grocery stores do survive just off that (and as someone else just pointed out, most loss leaders actually aren't, and they might be missing a big sales opportunity). Is anything you just repeated about the restrictions of the sale communicated by the store? No, and that's the problem. It's the store's fault.
And let's see, if it were you, you'd also ban kids, right? Because how would you know they are related? I've been conscripted to buy limit 1 eggs before when I was a teen. We were a poor family of 4. Would you interrogate and demand ID from anyone looking young? Can the store not deal with 2 or 3 customers buying the sale item up to the limit they set themselves?
And let's see, you say your corporation bans this kind of thing - how so?
And you ban extreme couponers by policy? Huh? Do extreme couponers have a badge or something? Do you ban use of any coupon? It's funny because except for store-issued coupons, those are all manufacturer's coupons. Read the fine print - the manufacturer will pay the store the face value of the coupon plus 8 cents handling fee! The stores make a killing off these extreme couponers buying overpriced items for the coupon discount. The only thing is that managers may limit them to 4 or 8 so that all the couponers get some rather than one clearing them out. By the way, I did try couponing for a while, but it just wasn't worth the time spent, and the coupons are usually for packaged foods which are not healthy. Also, those extreme couponing videos you see with the dozen carts of stuff for free are fake - it's all been revealed to be totally staged.
I think ... you just have way too much hate for customers. Just make good, clear policies, and you won't need to treat your customers like criminals.