Is it normal for somebody who had an impoverished childhood to be a hoarder?

My wife was poor as a child. Her parents were alcoholics. She was always scrounging; for food, for coal along the railroad tracks for the stove, for half used abandoned bars of soap in the girls locker room. As an adult for the last forty years she has been well cared for and has need of nothing, yet she hoards and stockpiles stuff like she's never going to see a store again.
When I go to the cupboard to get a bottle of aspirin several things fall out at me because she has stuff packed in so tight, usually two or three things stacked on top of each other. Sometimes things fall out just from the suction caused by opening the door. Same thing with the fridge. It would honestly be difficult to fit a cupcake in the available space right now.
Same thing in the medicine cabinet in the bathroom. Every time I reach in to get the nail clippers or a Q tip a couple things fall out at me.
She isn't bothered at all when these things happen to her, but it's very annoying to me.
Years ago I would clean out the cupboards and fridge when she wasn't around and throw out all the outdated bad foodstuffs. Then she would buy more on sale to fill the empty spaces. I soon realized it would save us a lot of money to just leave the cupboards full of outdated stuff, to take up space, so she wouldn't have to buy more.
Anybody else have similar experiences?