Speaking of rules, I recently flew through MUC airport. I had a few hours to spare before the next flight so I though I'd eat something.
You should know that I was wearing a mask, which is still mandatory at German airports. British and Belgian, too, but that's beside the point. Anyway, I found a breakfast kind of place that looked OK, so I waited in line to be seated. When it was my turn, the German lady handling the tables looked at me very sternly. I'm not good at reading eyes but there was no doubt here; she was upset. She started telling me in German that my mask was all wrong. *Nein!* You're not to enter with that mask.
What was wrong with my mask? It's the usual surgical kind, used by surgeons who try not to infect their patients while operating on them. What's wrong with it?
It is dizallowed!
She disappeared for a moment and then came back with a different kind, an FFP2 mask that looked stiff and unforgiving, and ordered me to put it on. *Jawohl!* I did, and she led me to my table, 10 or 15 metres away. She left me, I took off my mask, and I ordered food, and I never wore that mask again.