Dave-
Not to worry!
Chickens are omnivores...and they take that title very seriously. They will eat anything they can catch- including frogs, salamanders, bugs, worms, etc....and let us not forget they even eat mice. They are also often called rototillers and garbage disposals!!!!
My chickens get ALL the leftovers in our family. The only thing I really watch for is salt content. That seems to be one thing they don't watch out for themselves. So I don't give them all the chips that have gone stale....or I limit how much bacon they get etc.
Free range chickens are great in the fact that they do end up self regulating. You'll find that they'll go nuts for one thing, but if you have too much they go on to eat something else...like some dandelions or bugs! They might return to finish their treats...or not.
Enjoy your chickens!!!!!!
Sandra