Whilst I agree that feel putting your feet on the wall is unacceptable, I think the poster is more upset by the attitude of the crew member concerned and the way that she was communicating with the customers.

It is so easy to be polite even if you are having a bad day, and I wonder how many other people this staff member had snarled at that day!

I agree that most (in my experience probably 99%) of BA crew (from all fleets) are great at the job and have a lovely temperament, but the odd one or two over the years do make me wonder why they don't move on to a job they might find more their cup of tea.