RE: hot drinks
On the colder days I always bring a thermos of hot coffee or chocolate. I would rather have something to warm me up and keep me focused, so I can stay on stand longer.
As far as the smell of coffee spooking the deer, a few years back I had just poured a cup of coffee when an 8 pointer came in down wind of me and gave me an easy shot. It didn't seem to phase him a bit.