Because I forget them at home most of the time on the way to something else.
Additionally, don’t just take them when you know you’ll need them, do it before. Next time you need to leave your house to go somewhere, grab some and put them in your car. Done. Go put some right now next to your wallet or keys or literally on the handle of your house’s door.
Or just use the cardboard box approach I mentioned. You can’t forget to bring what’s already inside the store.