I'd like to think no one knows how the seashells work and the real joke is everyone just makes fun of people for not knowing (the writer didn't even know what they did and refuses to say anything other than how they came into the story)

I've purposely put three seashells in many public restrooms

Huh? I thought that was canon. Was that actually just a head fiction?

No they played that one pretty straight. You were supposed to be just as confused as MC. If they wanted you to think anything else, they would have given a knowing wink.

You don't know about the seashells? (muffled laughter)

... and the only kind of music that exists are jingles and showtunes

You don’t know how to use the three seashells? lol