Non-profit groups must have a handle on their workforce in order to serve their mission statement.
Without people power non-profits are dead on their feet and cannot help anyone, or any cause, much less themselves.
Then there are issues with paid employees and non-paid employees, who out ranks whom, who is the boss and who is the most important? If the volunteers feel slighted or realize they are doing more work than anyone else while the paid staff or partially paid part-time staff does little if any real work; there will be problems and once the problems start they just get worse and magnify over time.
Volunteers must come to work on-time as they have promised and they must be treated with the same respect as the paid employees.
Non-profit volunteers are subject to protection under the law in many cases as much as the paid employees.
Poor treatment, right-to-know, discrimination and sexual harassment rules and laws apply to volunteers too.
Many a nonprofit group has been sued for 100s of thousands of dollars for breaking these rules and it is the human resource director's responsibility to insure fairness in the workplace.
Just because you run or work in a non-profit group do not be so naïve to believe that you are somehow going to be able to operate under the radar and not follow the letter and intent of the law.
Please think on this.