No, through EAS (UAC) they can award up to ten bonus points to your atar, then they can add up to 5 bonus points from HSC plus (UNSW). So overall you can be rewarded up to 15 bonus points all together (assuming you are given all of the ten points for eas and 5 for hsc plus).
If you really want to do commerce at unsw, but don't get in, don't worry. You can always transfer into it. I suggest choosing another degree within UNSW and wait out a year so then they can consider you to transfer after. This way they won't look at your atar AT ALL, only the marks you get in your first year of uni. The degree you choose to study internally within UNSW doesn't matter, but I suggest you pick Bachelor of economics as it has a lower atar and it usually has the same classes in the first year as commerce first year, so credit transfers is possible there to save you time and money in your commerce degree once you transfer.
If you don't mind what university you want, but want commerce, then of course you can do commerce at usyd or Macquarie (or business at uts or wsu, but keep in mind wsu business isn't accredited, so no point doing business at wsu). Then you can be studying commerce and if you so choose, transfer externally after one year into commerce at unsw, again could potentially do credit transfer then. But keep in mind credit transfers from another university is unlikely SOMETIMES, but is still possible. Other wise you would have to repeat first year commerce at unsw, once you transfer externally.
Sorry for the long response but hope this helped!!! Good luck!!