I started to do it the other day at the grocery store but my wife was embarrassed by her husband putting cans of tuna on the produce scale so I had to stop, so I thought I would ask here.
At one point does buying canned tuna and chicken become lighter than buying foil packs? And most definitely spam as it comes in those thin walled cans. (picking one up is what got me thinking about this) There are 4 of us going together, so we kind of have a bulk option to consider. It may very well be lighter to bring one big 30 oz or so can than 5 or whatever foil packs.