I feel your pain, I do exactly the same thing, if I am smart I leave my husband home, less damage. He is one of those expensive specialty item guys. My biggest ticket items are specialty as well, but more in ingredients like concentrated pomegranite glase or garam masala spices, the husband grabs prepacked specialities that are killer, and he as well has a paper profuct obsession,..paper towels on sale,..if they are bounty I swear he died and went to heaven.
I have been starting to idiot proof myself. I found trader joes,..mostly because I can read the ingredients of all their products and know what is in it no big ridiculous alien ingredients. I have an obsession about avoiding high fructose corn syrup and hydrogenated oils amd msg and so on and it is easier to find the products there. But what I did find is that I get good wholesome food at way lower prices than the local chain food store. So now I buy my meat whereever it is on sale, bulk items at wholesale club and the majority at trader joes. I am going to start doing the farmers market too unitl my garden starts to produce.