Siri Jukebox - An Undiscovered Feature?

We keep our single HomePod mini in the kitchen. Next to it sits a cylindrical box that once held cookies that my wife now uses as a piggy bank. Every time she drops some coins in the box Siri responds by playing random music as if the coin drop was into the slot of an old style jukebox. This morning it was The Beach Boys hit, "In My Room".

Is this a Siri feature that Apple hasn't publicized or just a random mutation that affects only our HomePod?