The opportunity to have a communal barbie out-of-doors is everywhere to be found in and around Sydney: publically equipped with all the basic cooking kit, built-in tables and chairs and also toilets. Both generously provided and very well-used.
On the Hawkesbury you can even rent a barbie boat. (I should note that the one here is stuck on a sandbank, and will be unable to leave- according to our captain - for at least 6 hours).