Prefacing that I'm also not an American - and humour here can be a lot sharper/more brutal and often doesn't translate well across the Atlantic - if I did this to a friend in economy it would explicitly and only be because I was taking the pee out of me being up front and them down back - nothing nice about it at all! I would fully expect it to be taken as such, and I would fully expect the sort of comment that OP describes in return... all of which would be in good humour and with a laugh.