I had a rather irritating experience recently with Big W. I was comparing prices of microwaves and couldn't be bothered writing down the model, specs and prices so I was quickly taking pictures of the price tickets instead. Suddenly an employee approached me and asked if everything's ok. I told him that I need a microwave and was comparing prices with Target and Harvey Norman. I thought he would try price matching but instead he told me off. His exact words were "We only sell here, we don't take pictures" then turned around with a look of disgust.
I felt insulted over something that I've been doing for ages.
Ended up getting a Russel Hobbs 25L 900W from Target for 37$. So glad I walked away.
This is probably part of the "Big Change" that Big W is having.
I am surprised that you had an employee come up to you in Big W!!!!
I would have more luck finding water with a stick in there than someone to help.