I despise rudeness. When someone is being rude, it's easy to feel assaulted by that person. But just remember that rude people are usually rude to everyone, not just you. You can't change someone's behavior, but you can change the way you react to their behavior. Yes, kill them with kindness. Don't react to their rudeness. This will counteract their anger/behavior and make them look bad and hopefully they will see that. Try to rise above it and don't lower yourself to their position. But also, I know sometimes it can be really difficult to just sit there and take someone's rudeness. If they are just beyond reason, I will not hesitate to sling a little of it right back to them. Sometimes rude people do need to be put in their place. Rude people are generally control hogs and/or angry people in general. They need to dominate. Beat them at their own game. If you get angry, they win. They are being rude for a reason. To get you angry so they can have someone to shreik at. Like someone once told me...patience is a virtue. I found that to be very very true.
Kill em with kindness. Be so extravagantly kind, that they pick up on it. Thank them for their patience, kindness, time, in such a way that they begin to suspect sarcasm.