I don't know the situation in Australia but in the UK the legislation covered "Children and Vulnerable Adults". This included elderly people and those with learning diffculites for example so claiming they don't have specific activities for children would not get them off the hook.
The legislation has currently been put on hold here as the previous government failed to apply common sense to its application. Still waiting to see how and when it will be resurrected. At the moment the only obligation is to report anybody that is unsuitable to work with C&VA to the "Vetting and Barring Agency".