What do you mean excuses? It's just history. It's said for the same reason, because history.
I'm sorry it offends you but nobody in Australia is overly motivated to change something that has no practical impact and given you don't seem to be from a Commonwealth country I don't think you are entitled to complain about it either.
It's why some people freak out when someone "disrespects" their flag, why judges wear special clothes and why courthouses/government buildings are so frequently built to look impressive.
Such symbols perpetuate attitudes of deference and subservience to what the symbols represent... not for everyone, but they are effective on a lot of people, which is why they're still being used.
I'm sorry it offends you but nobody in Australia is overly motivated to change something that has no practical impact and given you don't seem to be from a Commonwealth country I don't think you are entitled to complain about it either.