I wonder if this is a third-world thing, soda contests for cash.

I remember when I was 12 in Bolivia, we had literal Coca Cola scratch off cards and had to collect bottle caps with the numbers to make a lot of cash. Kids would trade bottle caps, rumors floated about fulanito having the rare cap and he would sell it for the right amount, etc.

Been in the states for a few years now and never heard of something like that here. Then again I haven't had soda in the same amount of time.