Holden Commodore 2012: Servicing schedule

In the 18 months we have owned our 2012 Holden Commodore Equipe we have only done 10,000km. It had its first check at 3000km, had a nine months service and only had around 6500km on it at its first oil and filter change, and it is now 18 months old and I am told it is due for its 18-month service even though it has only got 10,000km on clock. The oils are supposed to be so much better today and last longer, so why do I need to service it so often?