good points on cardboard boxes and provisions and boxes on board.

We also never put cardboard boxes on board a sailing vessel, or even bring items home from Costco into the house.

Best to bring you own stout plastic bags , they do not take up much room, and are easy to pack.

The reason we do bring aboard card board boxes is that they can be roach hotels.

As to riteway, we now bare boat out of Conch Charters and run one of their several dock ' barrows ' over to riteway which is a short distance up the road.
When checking out, we take items out of the stores carts and put them into the dock barrow, and wheel the supplies to the boat. The store put our purchases
into normal plastic bags...., totally easy transition.

However, we do not sail with 8 to 12 people, there is just the two of us, and that might make a huge difference for transporting needed provisions.