One other thing that drives me completely crazy is when people pick up a perishable product and then change their minds about it and then leave it in some other aisle to rot. The other day I found a roasting chicken, still hot, sitting on a shelf with the dried pasta. I took it back to the deli and gave it to one of the staff.
I've found frozen stuff in other aisles and my worry is that one day, I'm going to buy something that has been put back in it's rightful spot, but prior to that it has been dethawing for hours and was then refrozen!! Because of that, I always take the 4th or 5th product underneath the one on the top.
I don't know how people can be so wasteful, to just dump perishable food in some other aisle and not even think that someone might end up getting sick from it, or just letting perfectly good food go to waste.
p.s. the chicken I returned was still smokin' hot so I think it was still safe and that's why I returned it to the deli.