Not sure what its like in Australia, but certainly in Scotland and the North of England I've often worn a kilt on public transport and nobody's ever made any comment. Its just not been an issue. People will only notice you as you board and alight, or on a long distance train when you go along to the toilet or diner. I boarded a London bound train at Newcastle in the north of England last year wearing a black kilt, and having found a seat, the first guy who passed along the aisle on his way to the buffet car was also wearing a kilt. A couple of weeks ago, boarding a train in Glasgow kilted, a mini-rabble of three young guys in kilts also boarded the same train.