Hi all,
I've done this numerous times. I would purchase a later flight for a lower fare, then standby on an earlier flight.
I don't believe that this is unethical. Here's why: The Terms and Conditions under which I purchase the ticket give me the right to stand by on the same day of travel. This is exactly what I paid to be able to do! This is perfectly within the guidelines on which I made the purchase.
The airline and I agree to a contract. I expect the terms of the contract to be upheld by the airline, they expect the terms to be upheld by me.
Of course, I risk spending extra hours at the airport waiting for my originally-booked flight. That was also the effect of the T&Cs under which I made the purchase.
- Tim in Hollywood