We use titanium cookware and dinnerware (made for backpacking, which we also do). The total weight of our mess kit for 5 people is about 3.5 lbs (kettle, 2 pots, 5 plates, 5 mugs, 5 sporks, 1 butter knife, 1 sharp knife (steel)).
Buy food and drinks local to the destination.
Fleece is lighter weight than cotton, and won't absorb water. Down-filled backpacking sleeping bags are even lighter. (A good 40 degree bag weighs less than 2 lbs.)
Aluminum framed camp chairs are lighter than steel-framed.
TPU air mattresses weigh less than most beds that come with a trailer.