I've found myself on quite a few flights in economy these past 2 months, both long haul international and domestic (trans-con or mid-con). On flights where I'm not driving at the other end, I enjoy having a few adult beverages, however there are typically only 2 regular drink services on these flights, one before/with the main meal, and one right after, during meal clean up. (of course there's one more on long haul just before landing with "breakfast" but usually I'm not in the mood for adult beverages then).

What's the correct / accepted etiquette from UA flight attendants for requesting additional drinks past the 2 that come on the beverage carts early in the flight? On other (foreign) airlines, I just go to the rear galley and ask whoever is there if no FA's have made a pass through the cabin recently, but know US carrier FA's can be less receptive to requests back there. On quite a few foreign airlines there'd be someone in the aisle in somewhat frequent intervals in case people want something, but not on any US carrier that I've ever seen.