Yes, it's legal to sell them.
The way they go about it is ethically questionable but some people, who have no idea about hi fi, wind up with speakers they feel proud of.
So, I guess it's no more unethical than some of the high priced cables I see being bandied about this hobby.
They do look impressive to the unknowing and, sound quality notwithstanding, that alone satisfies many people. Again, look at cables.
It's sort of like two addages:
"If something sounds too good to be true, it probably is"
and, for those who are happy with their purchase
"It's all mind over matter. If you don't mind, then it doesn't matter."