[QUOTE=WeekendTraveler;35118792]
I could see why years ago, when you had paper tickets and airlines didn’t know if you were actually going until you showed up at the airport.
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You used to have to call to reconfirm your flights, even onward connections. Was even required (and I got caught out in such) well into the first decade of the 2000s.
But these days, when everything is online, and airlines have great systems for managing oversold flights: what’s the point?
Probably assume that advance check-in ill yield a more accurate number of passengers who will actually show up.
Amtrak doesn’t require you to check in.
May not have assigned seating requirement, of perhaps even enough seats for all pax (maybe not now but a couple of decades ago)..