Sidenote
I never went through proper Customs on this trip.
Having a layover in Zürich seems to be a little cheat in the system. I was fully expecting to have to pick up my luggage, go through Customs, only to have to go through security again. Instead, I was directed to a Transfer Zone where I went through a small security with only my carryons, followed by an even smaller Customs where I was just asked where I was going, got a Switzerland stamp, and was on my way.
When I arrived in Hamburg, because it was an Inter-EU flight, I picked up my luggage, walked through a door labeled “Nothing To Declare” and found myself outside. So now there is no actual documentation of my arrival in Germany, meaning my 90 days as a tourist could potentially be much more. It won’t be as I’m getting my au pair visa when the tourist time runs up, but that’s an interesting little breach in protocol.