The burden is on you to prove something works, not everyone else to prove it doesn't.
Oh, really? I don't know if it does and did not say that so how can I prove it does?!
I did not know that logical statement NOT A is true by default until someone proves otherwise. Whatever A is.
As others have stated the burden of proof is always on the person making the big claim. No one can prove that vampires don't exist, so should you live your life as if they do? If yes, then what about the infinite amount of other claims to be made (unicorns/healing crystals/power wrist bands/purifying magnets etc.)
I can see Leo's point but it doesn't make it right.
Paul makes a claim about his product.
Pete says it doesn't work because no one's proved it works.
Pete might be wrong, just because no one's proved it works, it doesn't mean it doesn't but as Paul wants money for his product, he shoulders the burden of proof.
A similar debate occurs between atheists and believers.
Atheist: "I don't believe in God because there's no proof God exists! All you have is blind faith God does exist."
Believer: "You can't prove that God doesn't exist. All you have is blind faith God doesn't exist."
All I can say here is that there's no proof the de-scaler works so you'd have to be an idiot to buy it. I can't say for sure it doesn't work but it seems implausible.