Supermarket etiquette

I've always found it peculiar that, as I approach the supermarket checkout counter, there are magazines with covers blaring issues that it would be entirely inappropriate for me to bring up with the other people in line, or with the checkout clerk. For example, I would be ill-advised to turn to the nearest stranger and, pointing to the cover shown at right, ask, "I wonder what 'little mouth moves' they're referring to?"

And what if a male supermarket manager posed that question (or read almost anything else off the cover) to a female subordinate? A career-ender, if he's lucky.

Seems like an odd double standard; you can put a rude thing in someone's face but only if you hope to make money off it.