I suspect that might relate to the smaller english/canadian fluid ounce and imports. they're very close, you only start to easily see a difference around 5 ounces. I run a bar in Canada, and i catch inspectors and suppliers constantly playing fast and loose with Imperial and American standards ounces and pints. Canadian law saws if you are serving a pint of beer, it has to be a proper Imperial pint of 20 ounces, from the big English gallon, if you call it a pint. you can serve any size you want if you don't call it a pint. i constantly see competitors passing off 16 American ounces as a pint. The revenue guys check that your dispensing machines are putting out an ounce but won't tell you whether they are using a Imperial or Standard ounce, i'm pretty sure they're using American ounce devices when they shouldn't be. Supposedly we're a metric country but liquor and cattle definitely aint.