That's assuming you would otherwise only ever buy the sale items.
Of course, if I see <insert item> is on sale at a great price, I'll go to that store with the intention of only buying that item. I rarely go to a store just to browse what's on sale and if I do actually need something then I have to buy it regardless of its cost.
Case in point, I saw that plastic cups were on sale at a great price, I went to buy a case and it was ringing up much higher then it should've. She called the manager and he's looking, and clicking, and typing and a few minutes later he's like, "oh, you don't have $25 of non-sale items so you can't get the sale price" I was very peeved at this point, what should've been a quick in and out of the store was now a 10 minute saga. I said forget the whole thing and I'll get my cups my regular place.