Hi Grimnar
You read correctly.
I get my brass foil from tubes of tomato puree. It's great stuff to work with, doesn't tear easily and holds its shape. (The foil, that is - the tomato puree is a bit gloopy for model-making.)
I cook a lot of chilli, curry and Italian food, so I get through a bit...
Just squeeze out the puree into a container, cut the ends off the tube and split it open with a knife. Once washed, it can be easily flattened out into a sheet. I sort of 'scrape' it smooth with a metal ruler - a technique which would destroy other materials.
Hope that helps.