You say that volunteers are people who are passionate. They represent the organization that they manage simply because they're passionate about the organization's mission. However, it is a form of compensation. Actually, that's not the right word, but they derive a kind of advantage from it.
Isn't it important to make public any involvement with the government, whether that person is a volunteer or an employee? If there's a difference, I'll let you explain it to me.
In my mind, initially, take the Canadian Meat Council, for example; if someone from the council intervenes with the Minister of Finance, whether it's the board director, an independent lobbyist, or a volunteer, that's still lobbying. Should it not be treated the same way, in your opinion?