Christmas
Now just when you think that they had gone too far with everything else, you would have never thought that they actually banned Christmas. Christianity is one of the few recognized religions in China, a communist state which is officially atheist. You can pray and practice your religion inside your respected church, but not anywhere else.
This is because they do not want their citizens to promote anything that is not traditional Chinese culture. Oddly enough, they make a huge amount of money each and every year selling Christmas items to other countries that they manufacture en masse. We guess that they have a financial soft spot for the holiday at least.