I don't know if you can consider this a hack, or if it's widely known already, but using the KFC app you can order 4 pieces of chicken for $6.95 without buying a whole "Shared Meal" to go with it.
Go to Shared Meals, scroll down to "4 Pieces Original recipe ADD ON" (that you can swap for Hot n' Spicy if the venue offers it), and add it to your order. Then check out!
Full disclosure - I haven't actually added it by itself with nothing else and checked out, but I have done it with just $2 seasoned chips as well as regularly with the Deluxe Combo from the Colonel's Table menu. And I have always paid through the app instead of at the restaurant, for a little extra CBF factor for them to go through a refund process if they challenge it (btw they never have).
Considering 1 piece of chicken is $3 and 5 pieces are $12.95, getting 4 pieces for $6.95 is pretty good value.
Thanks. Great hack. I look forward to using.