Why do airlines care if you buy a roundtrip ticket and only use one leg?

I don’t fly all that often but I don’t like paying any more than I have to. I’ve read from other threads here that airlines are starting to crack down on people who buy roundtrip tickets and only use part of the ticket. Why should the airlines care (besides losing money)? What are they gonna do, force the traveller to complete the travel on the unused portion?

Well, it’s like this: Airlines know that businesses have money and people don’t. And they want to charge businesses alot more than they do personal travelers. So, they have to find a way to figure out which one you are, so they can gouge you accordingly.

One of the simplist ways they can tell is that business folks rarely stay over a weekend. Fly in Tuesday, out Wednesday. Regular folks like to stay over a weekend, to see whatever it is they’re seeing. So, short trips that don’t include weekends are charged much higher.

This would all work great except that a business could conceivably buy two roundtrip tickets that include a weekend, and use one of each of them, to do one trip that doesn’t include a weekend. And this can be cheaper than buying a single roundtrip ticket, because effectively they’re buying two cheaper personal tickets, instead of one higher business ticket.

Duplicate thread.