My Ford Focus Trend I bought in March 2013 has just had its 30,000km or three-year service, even though it's only done 13,000km. The service mechanic rang to ask if I wanted the brake fluid changed at $85 and the aircon sanitised at $185. I agreed to the brake fluid change but not the sanitising, as I have never heard of this before in all the years of owning and caring for cars.
With the broad spread of capped-price servicing, lots of dealerships are padding service bills with unnecessary stuff to shore up their income. I've never head of aircon sanitising but a Google search found a spray can of the stuff for $20. Draw your own conclusion there.