You know, same with mine, wouldn't step in it. A couple flew out of their door clear across their big run and then huddled over there for a LONG time, until I carried them back. So I ended up shoveling out an area of the near the pop door and scattered some scratch for them, and they then ventured out and now don't seem to mind it, and have been out all over the snowy pasture with the horses. I figure with big snows I'll just have to shovel a little area for them along with the walks and the driveway and the decks and the horse runs...can't wait for the next one.
Oh, the other thing. If your coop is a little small for the number of chickens to stay inside 24/7, you might do the other thing I did. I made them a little A frame out of a couple of old fence panels, covered that with plastic, and put it near their door so they could come out and still have a protected place to hang out when it was just getting too wild or ?boring inside. I hung some cabbages in there for them to pick at. It was easy and quick, stays pretty dry and protected, and they seem to like hanging out there, even if the weather's crummy.