My post doesn't assume anyone has not "worked their bums off" and hey, it's nice if you can get it!
The intent of the legislation was to assist first home buyers deal with the additional costs of building due to the effects on building materials when the GST came in. They extended it to include existing dwellings because the higher cost of building artificially inflated the cost of existing homes. It has remained in place for political reasons. It was to help them get a foot on the property ladder.....something that young ppl here in the UK are struggling with.
Most people when moving to Australia, will sell their UK house and use these funds, and hence in my opinion (and it is just an opinion) don't need that support if they have previously owned a house. I got the grant, so I don't begrudge anyone getting it, however all of these schemes cost money and I can certainly see the case in the UK where the generosity of previous governments have brought quite diabolical fiscal circumstances upon a population that are feeling it.
You do mention that you "don't see why I shouldn't be able to receive the grant as everyone else does for their first home." Only it would be your second home....which is fantastic and good on you for working hard to achieve this.....I just think it's poor policy. Again, I don't begrudge you getting it. I know that they are looking at discontinuing it eventually, so your timing will need to be right.