Earlier quoted context omitted.
Grown cats don't meow to each other. It's a noise they make to get our attention. Each cat must figure out, on their own, that meowing works to get humans' attention. A cat with deaf human parents would have never learned this, or would have learned that meowing doesn't work and to try something else.
Cats definitely meow to each other. For adults it's typically an aggressive warning, but it happens. It's also worth noting that kittens and their mothers communicate heavily via meows even when no humans are present. Food-begging is a pretty straightforward association from there.
You're right that meows are by default how cats talk with their kittens. They also bring kittens dead or nearly dead prey, as the first step in teaching them how to hunt. That they choose to use the same idioms with us I think constitutes an eloquent comment on how clever they find us.