If you really want to raise eyebrows, tell 'em how much the flight crew is NOT making, especially when the jerk sitting next to you starts in on how it is the crew's fault the plane is late, etc. And depending on your uniform, airline affiliation, etc., you can inform that jerk how much you are not getting paid to sit there and listen to him. When the person expresses surprise, ask 'em how much they paid for their ticket.

It can be a rather eye-opening discussion for these passengers and maybe, sometime in the future, that person may think twice about lighting into one of your fellow crewmembers, making that crewmember more pleasant, and thus making one of your flights just a little bit less difficult. Or maybe not.