A gentleman cut into the line just behind me at the airport-entrance security check. Instead of pointing out his lack of courtesy, I smiled. A lady wearing a floral dress and her husband in a white hat (we were in Goa), forced their way in the space in front of me. Again, I smiled at them. Airports have a calming affect on me.
My friends gave me exasperated looks. Two minutes later, we discovered that we had been waiting in the wrong line. The entrance for our flight was on the other side of the building!
Had I made a big deal of the queue-offenders, the joke would have been on me. I've observed that stress levels and rude behaviour are proportional to the lateness of a passenger and the amount of luggage they carry.
Be a little early. Carry as little as possible. Enjoy your travels.