What is the purpose of the concourse object-free area at Midway?

The concourse object-free area at Midway is designed specifically to facilitate emergency ingress and egress. This area is kept clear of any obstructions, ensuring that emergency personnel can access the concourse quickly in case of an incident. This is crucial in maintaining safety and efficiency during emergencies, allowing for rapid response to any potential threats or medical situations.

The other choices, while related to operational considerations at an airport, do not align with the primary purpose of the object-free area. Unrestricted vehicle access and parking for city vehicles would likely compromise the safety and accessibility of the space, while serving as a waiting area for passengers does not prioritize the essential need for unobstructed pathways during emergencies.