I solved this problem with my girls last summer. I added a hanging container of mixed dry food in the coop. I fill it each night when I go to lock them in, and remove it when I open in the morning. It contains wheat, pellets, wild bird seed, chopped peanuts, sunflower seeds etc. Keeps them busy and happy until I am ready to get out of bed.
My container is just a large fruit juice plastic container with a round hole cut in the side. String around the neck hangs it on a nail in one corner of the coop. Easy to remove etc. Hope this helps you.