Another thing you'll run into is they'll show you a menu listing 6 or 8 wines, but the truth is they only have one red and one white on board. Adding insult to injury, half of those have screw caps.
In fairness to the airlines on international flights, in some countries disposing of the bottles has become an issue. They often end up carrying the empties back to their home country. Not many people realize how much it costs to carry 100 lbs of empty bottles, thousands of miles.