The fear of someone judging you as greedy or materialistic, for charging money, is probably an aspect of spiritual ego. Of wanting to appear 'spiritual,' and thus living through a mental image of yourself as a spiritual person.
Which is really just another form of social conditioning, albeit a much more subtle one.
I'm reminded of Mother Teresa's prayer:
If you are kind, people may accuse you of selfish, ulterior motives; Be kind anyway.
If you are successful, you will win some false friends and some true enemies; Succeed anyway.