Wow I am so glad to find this thread, I could complain about Chadstone MAC counter MA's til the end of time.
I don't know if I should bother getting into it, but one girl there FLATLY REFUSED to help my friend and I, to the point where I asked the blonde guy to help us out, he called the same girl over, and she tried as hard as she could to get out of serving us - she was doing NOTHING. I mean hello, it's your JOB to try out products on customers - she lost a huge sale!
So, now I go to the Chapel St store only. It's seriously less busy. Sometimes you have to wait a little while, but someone will come up to you eventually. I was there last sunday, a lovely guy named Daniel helped me out, he was totally informative, actually taught me how to use certain products that I wasn't going to buy anyway since I already had them - he spent at least an hour with me. He was tall, dark brown shortish hair - couldn't really point out much else about him.
Also, another time I went there another girl with dark hair and GORGEOUS tattoos on her arm/back helped me and a few people I was with, she spent about two hours with us and was really HAPPY to do it. I knew her name but I've forgotten it now... there was also a blonde girl with long wavy hair that colour matched me the same day, she was very nice.
I would recommend any Melbourne person to go to the Chapel st store, especially because they have pro items! I haven't been to the city store or anywhere else though...
Hope that helps anyway!