Once I traveled London - San Francisco. At the check-in time, I was told that my ticket was upgraded to Business class. But when I just entered the flight, they checked my ticket and said mine has been upgraded to First class
And even after all the passengers got on board, the flight didn't take off for another 4 hours because of unfriendly weather conditions. They started serving drinks in first class even before the flight departed and in that 4 hours I managed to finish 3 bottles of Champagne. No need to ask, they keep refilling the moment you finish your glass. Too tempting