I feed crows in my area, peanuts hard boiled eggs, cat food, water as well. I won't be giving the crows junk food.
I haven't figured out where the nest. If I come near them when they are eating they fly off, which I expected.
A neighbor a few years back was shooting at the crows in a pine tree, I know this because I came outside and saw who with the pellet rifle. He knows darn well it is a crime to kill a crow. That day there was a big flock of crows in the pine tree talking, which he didn't like.
I am trying to see if I can get the crows here to work a food puzzle, out to get peanuts, so far no takers. I have gotten a response with a jar full of seeds topped off with peanuts, I put a lid on top of the jar and the crow took it off and got his/her reward.
answering question # 1, I feed crows in our yard, I have tried to see how they are doing, I have not seen any foot problems.
I did see the crows already at the feed chase off another crow. I haven't been able to discover anything else with the crows.