Unless already utilized to the max, the shower has a lot of room for travel storage, great for things you'll move outside anyway. Our shower is the kitty litter station, laundry bag, holds the portable stick vacuum (very handy!) and a gallon or two extra water. Could hang more from the walls. We usually sponge bathe and shower at gyms or the occasional park anyway, but not that hard to shuffle things elsewhere for that needed shower.
Really light weight chairs most likely won't harm the ladder, I would not want something heavy bouncing up and down out there. You could hang them there with the ladder folded up (ours is always up until needed.) Out of the weather sure sounds better.