In some locations bus drivers go "on strike" by refusing to take fares for a set period of time. The service is provided, they are paid their usual salary, but

In some locations bus drivers go "on strike" by refusing to take fares for a set period of time. The service is provided, they are paid their usual salary, but magically it seems no one caught the bus that day when we look at the figures! Work to rule is another way to do it. I personally find the concept hilarious.