A&W predates MacDonald's and KFC. It started in 1919 as a Root Beer stand.
It became popular at the end of the First World War.
MacDonald's started in 1940. The KFC franchise started in 1952.
A&W gave its franchisees a bit more control than later franchise system. So, the menu would be different from store to store.
PepsiCo bought KFC and later A&W. There are numerous restaurants in the US that combine the two franchises. I wouldn't be be surprised if the restaurant you visited was once serving KFC chicken.
*Pepsi sold its restaurants chains when competing restaurant chains stopped buying its soda.
As for KFC chicken: Apparently chicken produced by the poultry industry used to be dry. KFC used pressure cookers which would add moisture to the chicken.
The poultry industry changed chicken feed so that the chickens retain more moisture.
!WINE
RE: Lunch at A&W Restaurants - My Favorite American Fried Chicken Restaurant