It's because Americans mainly cook with volumes ("1 cup flour") and not masses ("100g flour"). Just look at any American recipe book - it will use volumes instead of weights.
Re:How SEO Ruined the Internet
by richjdsmith on Wednesday April 08, 2020 @01:14AM
(#22810267)
Wait, Canadian here, American's don't have electric kettles?
Maybe I've watched too many infomercials and soaps. I've reached a point where I know Americans don't have (electric) kettles, but a scale seems like a necessity for anybody who cooks.
(I guess there are lot of people, American, or otherwise, who just don't cook. So I'd understand in that case. But cooking without a scale just seems surprising. Even where I come from a grew up with a balance-scale with brass weights. Never hugely accurate, but always available.)