Children of all ages running rampant, old people shuffling down the aisles at the approximate speed of arthritic tortoises, housewives nagging their husbands either in person or via mobile phone, the shelves I wanted constantly blocked by people who browse for five minutes and then don't actually get anything from that shelf ... argh.

I second all that. *patpat* The nagging housewives are the least annoying to me, because the nagging, in and of itself, does not inherently impede my progress from Point A to Point B. (After all, some of them can walk and talk at the same time.) The rest... it's like a cross between bumper-cars and Sokoban.