The idea
Charities are required to be for ‘public benefit’. ‘Public benefit’ is not defined in such a way that the activities of the charity need actually be in the long term interests of society. This is particularly the case for religious charities.
Why is it important?
An example of what can count as ‘public benefit’ is providing speakers to go in to schools to teach children that the Earth is 6000 years old and that if they do not believe in the literal truth of the Bible they will go to Hell. This is obviously against all our hard won knowledge of the way in which nature works, so how can it be a public benefit? Is misleading children and credulous adults really a public benefit? Organisations with such aims should not be accepted as charities.