They operate all day from Redland Bay to the South Morten Bay Islands. They also go to Moreton and Stradbroke Islands. They go from Cleveland. They may go from Eagle Farm too but I'm not sure about that. I think the Whitsunday Islands might have them too, and other Islands around Queensland.
I'm not being a smart arse but how do you think goods and services get to various places.
There's also a dedicated Ambulance ferry, ( it carries people tho not an Ambulance ) and a Police barge that carries police vehicles to these Islands.
Semi trailers with building materials come over on barges, as well as dump trucks and energex crews. I've seen a semi with an enormous swimming pool on it, and full houses also get delivered. Woolworths deliver too. Thousands of people live on these Islands.
So yeah cars, vans, trucks etc need to get here. We have a school bus here too. It didn't drive over.
Have you heard of Fraser Island ? Many 4WDs get on car ferries to there also. And there are resorts over there that need goods and services.