Investopedia recently ran an article on tipping practices around the world. It's useful to know, especially in the US where many staff are so poorly paid that the 20% tip barely takes them up to minimum wage.
But they say this about Australia, which is way off the mark. Who doesn't leave at least a small tip in a restaurant in Australia?
Australia
In a country where the toilets flush backwards, it may not surprise you to find that Australia's tipping customs are completely opposite from those in North America. Essentially, there is no tipping in Australian restaurants. The minimum wage for servers is $15 per hour, which eliminates any pressure on customers to supplement a server's income. Small tips are appreciated for exceptional service or in upscale eateries, but they aren't expected. While this seems like a great deal for the customer, there is a downside. Taking tips off the table eliminates a lot of incentive for servers to increase customer satisfaction, and the sometimes-lackadaisical service can be frustrating for diners who are used to being catered to.
http://www.investopedia.com/financial-edge/0511/the-diners-guide-to-tipping.aspx?utm_source=financial-edge&utm_medium=Email&utm_campaign=PF-6/04/2013