Somewhat related: I happen to fly many transcon non-stops to LAS and have for many years. Most scheduled for 4+ hours. These are truly flights where having a sympathetic FA can work to one's advantage, because while you may be interested in tipping back a few, so is most everyone else, and in many cases you can have a competition develop for the scarce alcohol supply. I have been told that all flights begin with the same alcohol allotment, whether it is a 50 minute non-stop or an epic BWI-LAS or TPA-LAS ~5 hour adventure.

In my experience on these routes, alcohol will sell out in this order:

(1) All beer;
(2) Clear liquor;
(3) Brown liquor;
(4) White wine;
(5) Red wine

I offer this only because our forum is very interested in extracting every possible advantage. If you are on a long inbound LAS flight and, say, want to casually drink Heineken the whole way, I strongly suggest that you order them two at a time as soon as you can. IMHO, enjoying a beer that has warmed up a bit is preferable to being told, somewhere over Omaha, that the galley has one bottle of merlot left.