Skiplagging not so controversial
Didn't make a booked flight you bought and paid for? So what? Who's following you? They just want to make sure you're properly booked and registered at a nice hotel in the correct city according to your approved travel itinerary when you get off the plane. All that for?!!
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If you don't show up for the final leg of your booked flight, of course they will cancel your ticket. They're overbooked anyways and they can take standbys on the next flight. And you're not even asking for your money back in that case. Shrug and a pass. Plans change all the time. Got a work call. Bathroom emergency. Had to take a different flight.
Just don't send your checked luggage anywhere you aren't traveling yourself. You know how they hate unattended luggage at the airport.
They might call your name out loud at the gate a couple times before they seat standby passengers if you don't show up, but it's not as if there's a federal warrant out for you if miss your flight to the booked travel destination. And I'd highly discourage any name-calling in a public place anyways. If you aren't there, you aren't there.
Anything over and above old-fashioned train station etiquette (from before passenger airports existed) is overdone at the airport.