Why Do Valets Exist?

An advantage of valet parking is that it is possible to pack more cars into a given physical space, in what is generally known as "stack parking". The valet holds all the keys and can park the cars two or more deep, as they can move cars out of the way to free a blocked-in car.

Are valets still a thing?

Valets, like butlers and most specialized domestic staff, have become relatively rare. A more common, though still infrequent, arrangement is the general servant performing combined roles.

Does valet keep your keys?

Typically you will leave the keys with the valet. This is part of the appeal, you can just hand the keys to the valet and walk into your destination. Different valets may have different policies, but most likely if you ask them to return the keys to you, they'll do it.