Dear Aaron,
Just as in love, it IS better to have bought and not worn than to have never bought at all. Even at the cost that the shoe will one day hurt, because it no longer fits right, thus devastating you.
As to the other, it is ALWAYS best to be prepared for the unknown. I am currently buying and stockpiling ALL the shoes I can because after the great end of the Mayan calendar.....and doomsday, there may no longer be shoe stores for me to frequent!!! Never a waste. Always a preparation of sorts!