Travelers are flocking to airport lounges in search of complimentary food, drinks and perhaps most importantly, a chance to relax away from the hordes of travelers at the gate. The problem: plenty of other travelers are, too.

Armed with high-end rewards credit cards and fresh from years of big spending, more and more travelers are gaining access to airport lounges, turning what were once small, exclusive spaces for an elite few into a must-have stop for millions of passengers.