Andrew,
While I much prefer to cook butts on my WSM, for a Christmas goodie to each of my employees, I give them a pit cooked butt.
I use my pull behind custom smoker pit, and cook 16 butts at a time, each averaging 10 lbs or close to it.
When ready, I pull them and double wrap in heavy duty aluminum, then return to the warm grill so they can get a butt right off the pit. When the guest takes the butt, I put each one in a plastic grocery bag in case it tries to do any leaking. Letting them get a butt off the pit makes it more special.
If you are hand delevering yours, you can always put the foil wrapped butt in a large zip lock baggie. A one gal bag may be too small, so the 2.5 gal big bags will work for sure. This ensures th foil wont leak since it always seems to make a mess.