I also rarely go to Walmart before 10 pm (I rarely go there anyway, but still), because that store is like a nightmare in the day time. It's already a huge sensory overload as it is, but during the day, the store is full of 600-pound people with mullets and their entourages of 8 children, clogging the aisles. I can't stand being in there for more than 15 minutes during the day. But not at night. I'm more relaxed when there aren't many people around.
Also, this video is hilarious (and NSFW):