New York CNN  —  If you’re flying this holiday season and you’re noticing the plane feels more packed, while your wallet feels thinner, there’s a reason for that. A record 31 million passengers are expected to fly US airlines over the course of this week, according to Airlines for America, the industry trade group. And while many airlines have increased the available number of flights and seats, those capacity increases have not kept pace with demand. That limited supply, combined with the