Comfortable to wear, colors inside from

I've had a few Birkenstock Arizona as slippers.
A clear advantage is the good workmanship and durability.
As slippers keep their already 3-4 years, and even then you could use them even further.
But it also wants to have something nice new.

The only downside, and had my last pair is already also that the
Shoe on the light brown insole rubs off.
So you have the soles of the feet or socks breathed through light brown very short time below.
This has now not given even after a few months.

Although socks are there so that the feet do not get dirty, but something must now not be.