Saying "Wie geht's'" (how are you?) will certainly not be responded to with a short phrase such as gut (fine or good) but rather by a long explanation of everything on that person's mind.
You eat sandwiches for breakfast (especially Nutella on bread)
If you drive 4 hours almost in every direction, you will be in a new country which speaks a completely different language and has a new culture.
There is a transportation system, that is very efficient, running within each city and going to neighboring cities with buses, street trams, taxis and trains. Also special bike paths and walkways are made so one can go all over town.
you think it's completely normal to have a festival once a year, celebrating a Norwegian band and seeing thousand of people wearing "Turbojugend" denim-jackets – and you actually know what it means
you don't think it's weird that public transportation/taxi/police drive Mercedes, instead everything else is weird.
the radio says, "Queen Mary is arriving on Sunday" and you actually know who (or more so what) is coming
you expect people to drink a bottle of Jäger each and think it normal
you go downtown on a Sunday morning and don't expect to see a single soul on an hour walk (and not because of church, see above)