Many chikung schools do not charge any tuition. Others do charge tuition. Why should people pay to learn chikung?
Quite simply, if a large number of people practice the type of chikung taught in "free chikung schools" together, then more and more problems emerge as they practice. Good chikung teachers need to practice 20 to 30 years to develop their ability as well as have enough experience teaching students. Such teachers also need to have the right elements as well as the fate to teach chikung. Unfortunately, there are few teachers in our modern world like this.
In ancient times, few people could really practice chikung. Actually, true chikung can't be "taught" by a teacher. Most free chikung classes are taught by teachers who teach in a yin method that comes from the mind and consciousness so students need to 'believe' in the method in order to succeed. This is not a complete method.
Not everyone in ancient times who wanted to study chikung was chosen to be a student. The ancient teachers selected which people would be accepted as students based on the individual's wisdom roots, level of enlightenment and so on. It was very difficult to be chosen to study chikung and difficult to enter the world of Tao. It takes the unification of a lot of consequences for this to happen.
Free chikung classes are largely sensation-based, which means that one's mind is moving, so it is a yin form. Most free chikung schools don't charge for the lessons, but do have things which students buy to "enhance" their practice. For example, students buy things like tape recordings of the founder of the school, books, crystals, and so on. In free chikung schools you often never personally meet the founder. The founder of Falungung, for example, lives in New York City. Free chikung schools also have events for which a modest admission fee is charged. If 500 people pay this admission charge for one event, the school will get a lot of money in this 'innocent' way. Free chikung school also use a lot of logic, so the longer you practice, the more problems you will encounter in your practice.
A good rule of thumb regarding chikung practice is you should take a long time to enter the method; otherwise, you are using the wrong method and lots of problems will emerge. You need to raise the level of your body so you ultimately are dz you dz dzai and are a person.