It is very true that it is not an easy matter to make living solely through Yoga Teaching work. However, many Yoga enthusiasts have that ambition correctly or incorrectly.
Interestingly, there are some Yoga Teachers who actually are not making sufficient for their living but they feel their Money Status to be so important that they feel shy to disclose their insufficiency to others. For them, at times, making strong effort to make money seems lacking spirituality, but at the same time they give Money status so much importance that they feel necessity to hide their insufficient status from their kith and kin.
Another interesting thing is that another group of Yoga enthusiasts, mainly belonging to the teaching community, who have insufficient status. But, they watch other happy or stable looking Yoga Teachers and make an assumption that the later have a great income from Yoga Teaching. They actually do not have facts to prove this assumption. But, they feel shy to ask the presumed well-to-do Yoga Teacher about his/her true status.
The above mentioned confusion is more prevalent than what you may be thinking.