Today I started to study English seriously and I came across a good news that was almost ten years ago but maybe they've been keep going this rule since 10 years in this lovely cafe in France. I think It's a good idea to charge rude customers a little bit more than the others. Mr Pepino that is owner of this cafe and he said that "It started as a joke because at lunchtime people would come in very stressed and were sometimes rude to us when they ordered a coffee," . and then he wrote this blackboard for customers and suddenly this black board has gone viral on social media and was shared by journalist on Twitter. I think it's so important to be polite according to many cultures. it shows us Politeness is so important isn't it.