Hah - years ago, my aunt was stopped in a mall by a young Israeli guy selling these products. She mentioned that she'd been to the Dead Sea on a trip to Jordan and seen them selling similar products for a fraction of the price.
The salesman, unfazed, asked her if she was perhaps mistaken and thinking of the 'Red Sea, because the Dead Sea is in in Israel[1]'.
Thankfully, my aunt taught history, so she knew her geography well enough to know that he was just trying to pull the wool over her eyes.
[1] Which is technically true, since it sits on the border. But I wouldn't tell a Canadian that they were mistaken, because 'Niagara Falls is in the US'.