Maybe they need the protein & oil to regain good health after raising their young then moulting!
2013 photos & vids here
eff37 on Flickr
Hello David, l can't say that I have noticed our birds doing this, they feed from the seed, nuts, Niger seed and sunflower hearts. Maybe it is that they need extra goodness from the peanuts after rearing their young.
Beauty is in the eye of the beholder.