There's one at the Atlanta airport too. Not sure how long it has been there. I suppose it reduces congestion on the loop road from people stuck driving around in circles, waiting for someone to come outside. They won't let you park in the pick-up area to wait for someone.
It was unbelievably stressful when I had to drive around dozens of times while waiting for my sister to come out of the airport and get in my car. While driving around, I was constantly merging and merging and merging...and it was often difficult to merge with buses, lots of traffic, and poor visibility. Sometimes, I was forced to go the wrong way and had to find my way back onto the loop road. My phone finally died and I had no way to know if there was a change of plans and I might not find her at the front at all. The stress from that day...it still gives me nightmares just thinking about it.