I don't see ACCC as too weak. Unless perhaps you mean they are too weak to overturn their previous decision. The ACCC introduced credit card fees to make us, the consumer, more aware of the real cost of credit card points earning. Does anyone remember that gravy train? It's been an abject failure, points earning has instead just been continual slashed from credit cards, despite us knowing the true cost of earning those points with the credit card fees.
This is the thing. Why do consumers need to know the true cost of the merchant fee? We don't know how much airlines pay for fuel. Are they supposed to disclose the true cost of fuel? Both are business expenses and I don't see any difference.