If a host is not acting on their own behalf, this should be noted on the listing profile somewhere. If their property is being administered by a 3rd party property management company, it should be absolutely transparent to the guest that the person in the picture is not really their "host".
I would not want to stay at a property where I had to go pick up keys at a kiosk or that the host is not even aware that I am staying in their home. That is way too much like a hotel (pick your keys up at the desk, we don't care who you are just pay us).