M&P will stick to cardboard or any othert porous surface. You need to wrap them in soamething air tight (to prevent shriveling) like saran warp or cello. Then you can place that in a box if you really want to.
I agree if it only sits out a month or 2 it's OK but anything longer than that and I have experienced shrivel. That is why I would not recomend selling soap in a box w/o wrapping it, not knowing how long it will sit on a shelf before it is used.
Bret, have you ever not wrapped a bar of soap & let it sit for say 6 months? What did you experience?
I don't have any shriveled soap here to take a picture of, if I were at my mother-in-laws house I could show you some shriveled soap. She collects it & has some that looks shamefull. It shrinks & gets cracked & sometimes even bows.
The deal w/ them sitting out in the bathroom is that they are probably not sitting out very long w/o being used & exposed to water. You never know how long a bar is going to sit around when you sell it bfore it gets used. It could sit in a shop for a couple years or a person could do like I do & stock pile soap & pull out a bar I may have had for 6 months or a year. I know I have customers that will buy from me in bulk & dole it out over the next years as gifts so I need mine to be wrapped incase it doesn't get *given* for 6,8,10 months it's still looking it's best.
When I first opened my shop I made a bunch of loaves & was slicing them as the customers requested. The loaves That did not sell quick enough began to shrivel. I assume it is the water content evaporating when exposed to air.
The melting away in thh shower refers to people that either allow their soap to sit in water or are in direct line of fire of the shower head so they get soggy & mushy.
Another good reason to wrap your M&P is because the high glycerin content attracts moisture. It will actually pull moisture out of the air & to the surface of the bar of soap, this is called sweating. If your soap sweats it will be sticky & unsellable. Some climates are more inclined to sweating than others.
Ok, I actually found a bar of M&P my 5 y/o made for Halloween that has been unwrapped (but never touched water) since Oct. I placed it back in the mold so you could see just how much it has shrunk in 4 months. I also took a bar I made in May, unwrapped it & placed it back in the mold so you could see how there is no shrinkage after 9 months.