Last Friday, I was flying home from Denver; connection came in late to Charlotte in B, so I had to hustle it to get out to the E wing of the terminal.... turned out, my flight was a bit delayed, but a young soldier came up to the gate at the same time, wanting to make sure he'd not also missed his flight (and to double-check on me to make sure I didn't need the IV out of his pack! lol...) We chatted a bit, he was absolutely jaw-dropped that I knew where his hometown was, so we continued to chat until we boarded the plane.
I happened to be in the back of the plane, he was at midsection. It was a short hop, so drinks were only served on request. The stewardess swiftly passed through the cabin, most were ordering water, but the soldier ordered a beer. I happened to hear her tell him I'll have to get you change, then she headed to the aft section where the beverages were... I caught her attention, and paid for his beer for him. That had her caught off-guard, too.... I would have thought that it wasn't that unusual, but it surprised her. She returned him his bill with his beer, and slipped back to me later with his thanks.
I'd never seen or heard of using sign-language like that.... better than nothing, sure, but, I'd rather just head over and chat w/ 'em if we've got a moment.....