Don’t see many Germans wearing Birkenstocks

I (American) have been in Germany two weeks and have seen maybe 4 people wearing this brand. I’ve come to 3 conclusions: 1) Birks are so overpriced the average German can’t or won’t pay that much or 2) They’re overhyped as orthopedically great and the Germans already know this or 3) not considered fashionable

Any thoughts?