Buy yourself a pair of sunglasses with a hidden camera and recording device.
If a stewardess or the lady at the checkout seems to be a so-called B!+ch, then record their every moment.
Whenever you feel ready to BLACKMAIL them, do so by demonstrating to them what you just did and that you can easily get them fired by their boss if they do not comply with your simple requests [like asking for a meal or asking the checkout-lady to stop nail-polishing].
