Joe, why not take a couple machines to sell? And you could use them to demo/sew. I also agree with the hand-crank ideas. Why not do a drawing for a free bag? How about having hard candies or cookies? Can you monogram bags for people? Since you have a lot of fabric cut, why not offer an option to let people pick their own squares for bags, get the sales price, and do them at home and send them? Why not make potholders while you are there out of the same fabric? Just take pre-cut batting and backing and maybe binding. People might buy a set: bag and scarf, or potholders and place mats. How about a tote bag with a quilt for a child's doll or even a tote bag and baby quilt? See how
Christmas stockings would sell. All made with the same pattern.
When I did craft sales, the best advice I got was: "cute sells".