the QCIA has a FREE, "While You Wait", Cell lot-- perfect for picking up passengers. Simply wait for your party to call you, to tell you that they have arrived in baggage claim. Then, zip around the frontage road and pick them up curbside at the airport doors.
c/o Quad City International Airport,2200 69th Ave., P O Box 9009 (Airport Frontage Road/Skyline Inn) Moline , IL 61265 United States
Use this cell lot, adjacent to Bud's Skyline Inn Restaurant , and when your party lands and gets their bag, they can call you and you can go pick them up on the curb!
All airlines at any airport counter close check in 30 minutes prior, at which time the traveler is required to be in the gate area as stated on the contract of carriage. This is not unique to the QC. Read more
If you're going to be later than 30 min before a flight, have your ticket already, no one is at the counter and the kiosks are shut down. "customer service". Fly out of anywhere else if you can.