Questionable sales practices?
 

A couple a scenarios:

1. An airline charges reserved seating fee. Pax 1 purchases seating and picks seat from map. Price $100 ticket, $30 seat, total $130. Days later, Pax 2 purchases ticket in same class for $150, and is offered seat map with Pax 1's seat and more available. Pax 2 purchases same seat for $30. Total $180 for airline. Pax 1 is re-assigned seating, offered refund for seat reservation. Airline is ahead as it made more money on the ticket difference than the seat fee refund.

2. Airline sells Business class faster than Economy. Business tickets sold out but continues to sell them at higher price. Consequently downgrades lowest paying business tickets to economy.

You see where I'm going here. Can airlines run this sort of scheme to increase bottom line?

I'm confused.

The airline sells Passenger 1's seat reservation to Passenger 2 at $30, and has to refund the $30 to Passenger 1 (and find him/her a new seat).

How does that benefit the airline? If it had offered Passenger 2 only the seats that were available (i.e. not including Passenger 1's) it would have collected 2 x $30.