Tried to Google it for a while without conclusion.
Today I am billed 15% on the bill as Public Hol Surcharge, which I believe is a forced tipping. Normally I would be okay with this but the experience was regrettable because of the wait time and another billing issue, therefore, I wanted to file a complaint anyway. If there is an easy way to just tell, e.g. ACCC, I will try it.
Following legislative amendments in 2013, restaurants, cafes and bistros that charge a surcharge on certain days do not need to provide a separate menu or price list or have a separate price column with the surcharge factored in. However, the menu must include the words “a surcharge of [percentage] applies on [the specified day or days]” and these words must be displayed at least as prominently as the most prominent price on the menu.
If the menu does not have prices listed, these words must be displayed in a way that is conspicuous and visible to a reader. These measures apply to pricing for both food and beverages.
Source:
https://www.accc.gov.au/media-release/misleading-menus-invit…
Previous discussion
https://www.ozbargain.com.au/node/186084