[ghaff]

Hotels do tend to have a cancelation policy though (which is increasingly a day or two in advance rather than 6pm day of even for for not-charged-in-advance flexible reservations). You pay in advance for tons of other services (concerts, plays, etc.) and they're often non-refundable. Trains and transit also pay in advance in my experience. The main difference with planes is that, while you can pay for a ticket at the airport, it will be expensive, there's a decent chance they won't have a seat, and you'll get the worst seat choice.

Yes, there are a few services you post-pay like restaurants and taxis but you probably don't want to make a practice of running out on your bill.

Rental cars are something of an outlier in that, in the US, you can mostly book with major brands and just not show up with no penalty.

[stavros]

It's not about prepay VS postpay, though. It's about whether you HAVE to prebuy or whether you can pay at the door. Planes don't have the option to just show up and buy a ticket.

[ghaff]

>Planes don't have the option to just show up and buy a ticket.

Sure they do. Maybe not literally at the door because you have to go through security first. But they'll sell you one at the ticket counter if there are seats available.

[stavros]

Will they really? As far as I know, they stopped doing that years ago, but I might be wrong.

[rtkwe]

They'll still do it but most planes are oversold already to increase utilization, some of the airline's high rewards levels allow you to force your way onto planes too.

[throwaway290]

I've seen people buy tickets at the airport with cash before same day flight this year. I came to the airport and changed my ticket to depart on that day once.

[banannaise]

> Hotels do tend to have a cancelation policy though (which is increasingly a day or two in advance

Right, that's what the deposit is for, and that's how airlines would presumably do that.