Restaurants don't need turn over to make money, they need people who will order dinner and then order more stuff until the place closes.
Unlike Americans we do get drunk in restaurants because we drink alcohol while eating and this can last for days.

You also need reservation for a table in a dance club, because when you drink your stuff can't always you be in your hands, how are you gonna grope the pretty ladies?

That being said, restaurants are usually used by large groups of friends hence the reservation. 2 person reservation is a joke and those people should just eat junk food and not take up valuable seating space.

:) Welcome back