Empress:

Pretty sure that Fly Boy and I witnessed this in Puerto Plata (Dominican Republic) last year. An older married couple told us they did it regularly. In fact, the day we saw them happened to be their second bump, and they requested to be put on the list for the next day as well (didn't hear what the AA agent had to say about that).

I say more power to them - the airlines profit with even more regularity by overbooking flights, betting on no-shows.

-matintin