That is only correct for a very small number of hip cafes and restaurants in certain districts tbh.

You can employ germans indefinitely without "proper" contract as well through something called "Minijob" and the majority of cafes and restaurant skirt the law and let you work without paying taxes "illegally". Most of the ppl working there are students or in between careers. Only a fraction of the staff will be employed permanently with "real" contracts.

source: worked in the industry there for 6+ years