What is the point of a storage locker?

I don't understand the purpose of storage lockers.  

Don't get me wrong, I love love love Storage Wars. I am also fully aware of the general purpose of a storage locker.  It basically boils down to this: You pay good money to store crap that isn't good enough for you to keep in your home.  Eventually you forget what you are storing, so you continue to pay good money to store crap that is old, outdated and that you don't even recall.

Did I get that right?

Storage Wars has taught me one thing- frequently people store money and valuables in Storage Lockers as well- which blows my mind even more.

Really, truly- I don't understand why you'd pay for a storage locker for more than few months in the midst of a move or something of that nature.

As is, I can't remember some of the items I have in boxes in the closet!  At least those don't cost me a monthly fee to store!

-Kristen