The only time I've ever been carded (wasn't in F) was aboard a UA flight back to the UK last summer, no questions asked when coming round with drinks but when collecting I was asked if I was old enough. Then the FA made a sarcy comment about whether 'you'd like a little milk dear' during the second drinks round.

I hate the way the East Coast US (in particular) seems to be paranoid when it comes to alcohol My experience of carding is limited on the west coast ^