> i imagine they don't appear on public places like linkedin

Can they do that? Just hire through a small network of people in the know? Sounds like a recipe for cronyism.

I'm not sure about Italy but in the UK companies legally have to advertise a job publicly and, if they receive an application that meets the criteria, I think they have to at least consider it, if not conduct an interview. That's not to say there is no nepotism, but there are measures to control it.