I'm not sure that has been tested in court yet. If based on precedent, I would assume it would also be legal, but it would take a brave soul with a lot of money and free time to find out for certain.

SCOTUS could always overturn the existing precedent but if we assume they won't then it's legal right up until someone gets injured as a direct result. (Unless it somehow ends up running afoul of our ridiculous obscenity laws? I doubt it but you never know.)

Agreed that anyone who decides to demonstrate the above is definitely going to want plenty of money and free time at their disposal.