> A couple years back I scored absurd amount of Spaghetti Os this way, paying effectively negative money. The only downside is I ended up with a lot of Spaghetti Os :'(
Experiences like this have taught me to be careful about over optimizing. If I want one of something, and can't use (or don't want to use) more than one, it doesn't matter if buying two (or more) costs less than buying one; I should just buy one.
Yup, and often those tempting bulk discounts, if calculated, only end up saving a few cents or a dollar or something, so the trade off becomes -- Do you want to be payed 50 cents to store extra supplies at your house? Sometimes that's a good trade-off, but often it isn't.
Bulk-buying mentality is so prevalent in the US, it can sometimes be hard to avoid, and I think US urban planning has a lot to do with it as well - e.g. in many cities I've lived in the US, it would take longer to walk to my car than to walk to a grocery store when I was living outside the US, so you get trained to focus on economizing trips.
Some of it is holdover from various economic depressions that are holding on tight to our collective habits.
My wife and I both favor bulk shopping for a majority of our household goods, and when we pondered why, it came down to our families having done the same and followed that thread to our grand/great-grand parents that lived through the great depression.
Having bulk food/household goods means that at any point, if income halts for any reason, we still have X number of meals/tp rolls/litter changes before we enter the danger zone. That was reassuring when we were living paycheck to paycheck.
I do agree on urban planning being a part of it as well. It's a 15min drive to my closest grocery store, and 10 minutes of that is driving out of my neighborhood. Walking to the store is nearly impractical, and generally not safe due to the lack of sidewalks for a fair stretch of the main road.
I also think US (ex)urban planning has a lot to do with it as well. It's influenced by/influences the extra hauling capacity of the over-large median US household vehicle(s), the extra square feet of available/dedicated storage space inside homes, etc.
I have friends that "need" big SUVs if only for their Costco/Sam's Club trips. Whose homes by square foot would be palatial mansions and palaces to royalty of many previous generations, but are cookie-cutter one of hundreds in over-vast neighborhoods full of them, with rooms dedicated to bulk goods storage. It's a fascinating world.
Experiences like this have taught me to be careful about over optimizing. If I want one of something, and can't use (or don't want to use) more than one, it doesn't matter if buying two (or more) costs less than buying one; I should just buy one.