Greys will scratch at the bars and especially the floor of the cage wanting out, my grey will still do it from time to time and she is 6 years old. I think she needs more time out of her cage, my grey comes out when I get home from work and is out for 4 or more hours every evening and more on weekends when I am home, too much time spent in their cage is not good for them. They need and want human interaction if only to sit by you or be close to you when you are doing things even when you are sitting and watching tv.
Yes as said by others peanuts are only a treat, it cannot be their only food, provide a seed mix, pellets, fresh foods like vegetables, rice, grain, legumes and some protein, browse thru the bird food room for ideas and suggestions of what to offer, save the peanuts for training or rewards for good behavior.