I think that for many people, feeling bad about charging for something "spiritual" isn't the core issue. The real problem is charging something for ANYTHING. If you currently work for someone else, ie. are an employee then you are letting your employer do the hard work of convincing people to pay something for something else of value.
A massage person who enjoys thier job in a company that charges for massages would likely also feel bad about going out on thier own and "charging" for massages. It's the same service but now THEY are asking for money for thier service instead of relying on someone to do so.
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