Ahem, explain these ads?

[DontEatTheVolesKids]

here

and

here

among others by same seller.

Yikes

Is it no-used-underwear subterfuge, despite claims to the contrary? Or a cheap way to advert self for roles in porn films?

Seems like a nice boy.

Is that said with lecherous intent?!

It's along the same lines as the well worn shoes.
You sell something to people who have a fetish for such things, describe them for what they are; sweaty, worn etc but then cover yourself for the legal bits by saying they will be washed prior to posting etc (of course they won't)