Exactly, I have heard it a hundred times. Also, when people put fencing under the coop instead of a wood floor, critters get in. I even had a raccoon break a single pane window with a older 4 pane, and haul out my chickens one by one all night long till most of them were gone.
1/2 cup of food for a large rooster is no problem. Measure out 1/3 a lb and that is what a rooster will eat easily. Chickens will not over eat. He should be able to go into his coop at night by himself.
Try giving them ground up grain called mash. See if you mill grinds it. They use corn and alfalfa and other grains mixed with vitamins and calcium. Its called layer mash. My birds don't like pellets either. They might eat it if they were starving.
50 lbs seems about right for their ages. When they get to be adults you will need about 1/3 a lb. for each grown bird a day, so, about 120 lbs of food a month, possibly a bit less. Feed in hanging feeders and that helps with waste.
One rooster needs at least 10-12 hens to mate with or the hens will be mounted too much and will start to loose their feathers. It is cruel to have too few hens for a rooster for the health of the hens.