I live in a retirement community of 110K where "seniors only" hours are, as you can imagine, madness. I needed to pick up a prescription at a grocery store pharmacy and thought I'd nip in at 7am during senior hours since the pharmacy is also open early. I got there at 6:55 am and the lot was full, with a line of customers farther than I could see (with people crammed together, no less.) I stood off to the side waiting for people to file in, but after 18 minutes with no let-up, I begged the staff member guarding the exit door to let me get my prescription, which she kindly allowed.
I guess the early-goers figure they might find items that are quickly sold out after being restocked overnight, but I'd rather chew glass.
(Granted, I say this as someone who can afford and has been exclusively using grocery delivery, but so can most of the line-standers.)