Yes, you can put a chair in there if you rearrange a bit. Unless my memory is off I seem to remember someone on here having two people in chairs....maybe it was those air mattress chairs.
We have been in Steve's (Stid's) sawtooth with four of us around the stove in chairs, Steve and his wife in the taller style that get you up off the ground and Luke and I in thermarest trekker chairs. It's a little tight, but certainly doable if you can roll or move bedding out of the way.