One of the United Airlines ramp agents was pacing back and forth outside, from the front to the back of the plane, holding a giant sign saying: “THANK YOU FOR CHOOSING UNITED.”
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Apparently this is a new campaign this month by the airline to thank customers. A bit of surprise and delight.

A source, who was not authorized to speak with media, told TPG that United kicked off the campaign in July to let customers to know how much it cares and appreciates their business.