" If you have a mind-blowing talent, you want a million bucks for it, don't you?" That line, if you don't know already, was said by John Lennon. It is beautifully phrased as a question, leaving intact the possibility that the conclusion is false... but also allowing it to be the logical conclusion.
" If it's spiritual, it should be free!" Who has not heard or felt that sentiment? Yet, of course there is no real logic at work. Spirit by definition means free, unbounded. What people might mean is that time spent in spiritual pursuit or expression should be free, and many cultures have traditions of keeping their core spiritual instruction free.
How does one then resolve the issue of charging for attendance at their spiritual practice? Does this not contradict or debase the practice?
For myself, what matters is the approach. If there is no mis-representation, and one is true in one's approach to the art as a spiritual practice, then it becomes inconsequential whether one's time is being paid for, in terms of the art. The act of engaging in the spiritual practice removes oneself from those parameters. However, one is in a certain place at a certain time, and there are conditions set that allow others to be in close proximity!
The quote that captures this reality best was ( I believe..) made by Chuck Berry when someone pointed out that three thousand dollars was a lot of money to get paid for on hour's playing. " Playing?, said Chuck. " Man, I don't get paid for playing, I get paid for showing up!"