MAD has three. As long as CO had two flights per day (just ended for the winter ) two were on duty each day. Although they do greet some BF passengers, and come on board the aircraft before takeoff, I think most of their duties are with arriving passengers.

One is particularly assiduous about hectoring the baggage handlers (civil servants!) to meet CO standards for luggage on the carrousel within a certain time of landing. A thankless job. I know CO has shower arrangements at an airport hotel, so I imagine the concierges take care of those logistics.