How important are scratch grains ? I have 8 , 11 week old birds in one coop , and groups of 3 in 3 separate coops . all of the birds have adequate nest box , run and coop space . the floors in the runs are dirt and inside are shavings . The 11 week old birds are being fed grower/finisher and the adult birds are getting layer feed . I also supplement them with Oyster shell and leftover kitchen scraps ( only about once a week ) Do they need scratch grains , if so do i free feed or just give them some on occasion ?? Thanks I also throw them some fresh grass every other day .