Is there racism in Adelaide? Yes, as there is in most (perhaps all) places. Some people go through life not experiencing it or noticing it and others get a hard time because of it (as in most or all places - there's a trend emerging here!)
Anyone coming here thinking they'll never hear a racist comment may well get a nasty shock, but anyone choosing against coming here because they suspect they'll be discriminated against might miss out on moving to a very welcoming place. In short, it rather depends on how well you settle in, how sensitive/resilient you are, how observant you are, how lucky you are in the people you meet and how discerning you are in the people you choose to associate with!
I am half maltese i did live there for 2 yrs 2001/ 2003 i was born inthe uk experianced a little name calling at school and thats about it really never experianced anything in work places and i have worked in the mining industry and transport industry, places where you would expect a little bit . Whilst living in malta i found it hard to get work as i dont speak fluent maltese so i learnt maltese, This i felt was a form of discrimination as all maltese speak english as a second language. I totally agree with your post.