Junk stores, hardware stores, scrap yards....
What you said really is true Pete.
I always have the intention of using every bit of junk I ever bought, found, was given or dragged home from the dump for something.
However. I have sometimes found myself picking up things that are real junk just because of "There must be something I can do with that!" type thinking.

I also have a tendency to collect multiple versions of items as I search for the best one.

Quite a bit of the stuff got used, some of it got used a lot.
Some of it also got either sold off, gifted to unsuspecting innocents or returned to the dump whenever I moved.

Big Edit:
Having an inventory of emergency supplies is not hoarding. It is simply basic preparation.
It is quite separate and different than my junk collecting habit.