Under-buyer or Over-buyer?

When I first saw this Unclutterer post about whether one is an over-buyer or an under-buyer, I automatically thought that I was an OVER-buyer.  Why?  Because I love to shop.  I've become addicted to shoes.  Seriously -- I have a problem.  But then it turns out that for the most part, I'm an UNDER-buyer.  I do things like go and buy toilet paper when there's a quarter of a roll left.  Or dish soap when there's so little left in the bottle that I have to sit it upside-down to get any out at all.  I do have an annoying habit of throwing food away that has passed its expiration date, but I think that's more of a function of me not cooking at home enough, OR, that when I do cook, sometimes I cook only the things that require the absolute minimum amount of effort, and then unfortunately, other things go bad.  But, otherwise, I'm definitely an under-buyer. 

A couple of criticisms that I have about those questions are that:

1. Sometimes you DO have to run to a bunch of stores in preparation for a trip, particularly if you're going somewhere where the season is off from where you live. 
2. Sometimes people DON'T stock up on things like saline, toilet paper, gas, etc., because they don't have *that* much cash available, or because they don't have the storage space.  My parents have enough TP and paper towels and bar soap stored in the house to last them the rest of the year, but that's because their house has tons of storage space.  I have NO storage space, so I pretty much buy things like that as I need them.  And while I'd rather fill up my tank with gas when I do go to the gas station, I don't feel bad about only putting $10 in my car because I drive so infrequently that $10 worth of gas is going to last me a LONG time. 

But, nonetheless, I'm a UNDER-buyer.  Interesting tidbit to know about myself...