Why do these products exist, then?

[AbsoluteApril]

My question is: Why do products like Shed-Ease exist if you're not supposed to soak them? Why do Jump Start and Repti Boost exist? Are these companies just knowingly selling useless products?

They want to make money. Yes, they sell some useless stuff. They see something people struggle with (humidity - bad sheds) and so they bottle water with some 'additives' and market it as something that will help. Is it needed? no, not in the least bit. Do they care? no, they can sell it and make money.
Heck, people buy bottled water. (hehe)