A premium offering in Admirals Clubs or several years has been guacamole and chips, but that’s available not because American is willing to make that (very modest) investment but because the credit card that offers club membership is a Mastercard and Mastercard pays for the avocados.
If you want chicken nuggets inside an Admirals Club, they have those! But they’ll charge you for it. Indeed, they’ll overcharge you for it.