Hey, guess what? A cafe in French tourist town Nice has decreed if you're mean to staff, you'll be charged more for your morning coffee.
The Petite Syrah charges €7 per caffeine fix if you simply place your order, €4.25 if you add a s'il vous plait and a teeny tiny €1.40 if you prefix the whole thing with a friendly hello.
Now, some people - probably nice people - are probably thinking: "what kind of douche doesn't say hi, please and thank you?" So, as an ex-barista, allow me to answer this: LOADS of people!
When you work in the service industry, a lot of customers are convinced manners between you and them are bunk. In my time, I cleaned up sick, monitored wild children and once even called an ambulance without a word of thanks or even a tip. But would they have considered their manners - or lack of - if it had made a difference to their bill? Perhaps.
The Petite Syrah has the right idea - make respect result in a better deal and everyone gets what they want in the nicest way possible. Why hasn't someone thought of this before?