I think it's more the opposite, no? You go to the store for something you need, but then on your way out you pick up a bag of chips or a chocolate bar or whatever. I suspect that's why they often put them on display in the check-out line.
At least with my young single male peers, trips to the store are primarily for beer or tobacco or sugar. The 1 & 2 of video game junk food cross sponsorship has messed up a lot of their bodies