Originally Posted by terenz
My bet would be that per capita consumption of pop/soda has gone sky high. I remember the standard 7-11 Big Gulp was a huge serving 20-25 years ago. These days, it's small and towards the large end of middle in fast food chains, where you can often get free refills!
I remember back in the early 70s when McDonald's introduced their "large" 20 oz. soft drink. Before then, it was 8, 12, and 16 ounces.
After applying discounts from being in their rewards program, Speedway gas stations offer a 58 cent 44-ounce fountain drink all summer long.