I wonder if that's the "a single potato (or corn or whatever) chip in a box" challenge thing. I once considered buying it, but it seems so stupid to buy a single bloody chip for the price of several ordinary whole bags of chips.
It's Comikey, so purely online, right? I wouldn't believe it if it was on paper and thus physically in stores. Purely online, I can just barely believe it.
No, I still don't get the armpit thing at all, personally. I understand rationally that they are arousing to some people, but to me these people are just raising their arms a lot.