I had a little tete a tete with an American cabin crew the other day. Pressed my call button twice within 15 minutes and got a "I am busy" response after the second ping, to which I replied, I am thirsty, should I help myself ??

She turned her back without a response.

When the Captain did a short walk about, I mentioned it to him - never did see the crew member again for the entire flight...but I did get a top up, in fact several... oh... it was a longhaul and I was in F !

Thank goodness the American culture of service industry tipping has not been extended to having to tip cabin crew !!