I would not have wanted to be one of those 4 airline employees who had to sit in those seats.  I'm sure they got an earful from the other passengers.  Just makes me not want to fly period if all airlines are allowed to kick off paying passengers for these types of reason.  Those 4 employees should have found another way to Louisville.  I think the airline could have upped the ante more or if any of the four random people didn't take the offer, offer it to the next random person or see if anyone else would be willing to get bumped for more money.