taking the soap bars out of the wrapping and tucking them around also is a two-fold job. If left to 'air dry' out the wrapper, soap will harden and last longer, too!
Personally, I tuck in used fabric dryer sheets.....my quilt room is in a well-dehumidified basement, but you can never be too careful. Once in a while, I will also spray 'clean linen' fragrance bedding sprays.