It is good that you found it, Cat, but what would you do with that much butter if your power went out? I've never kept more than 12-15 lbs of butter in my freezer at one time and it gets used within the year. If my power went out during the summer, I'd probably lose whatever butter was in the freezer at that time. I never really thought about it until I read your post.
I tend to think of cooking oil/olive as being the fat that I store, since it is shelf stable (though it can still get rancid). I suppose in an emergency, I could trade a pound of butter to someone without any for something else that my family might want...
With the meat/veggies in the freezer, I can cook it as it thaws and can up what we can't use promptly...I can't do that with butter, though!