Mine eat more too. It's because there are no bugs for them to eat and they need to eat to stay warm. I feed mine cracked corn to help keep them warmer. I also put plenty of straw in their pen and house so they can keep warm.
I have 13 birds, and they don't eat nearly that much!
I fill my feeder with just one coffee brew pot a DAY! My ground is frozen, so I know the bug population is down.. I do feed them a couple handfuls of a mixture of BOSS & cracked corn.