There have been recent moves in the UK by some consumer advocates (notably Martin Lewis) to obtain refunds of fees that they believe have been unfairly or illegally levied in their accounts. For a fairly unusual, but very dramatic, approach read this article where the baliffs actually went into a bank branch (thanks to Stuffem).

This is driven by UK law that fees and charges must be no more than actual cost of the activity being undertaken.

I am not sure of the law in Australia on this point, but some of the fees and charges being levied by the banks do seem excessive ($35 for a returned direct debit?). All banks would have undertaken full ABC (activity based costing) analysis and so would know how much these activities truly cost. Whether the true cost is the average cost or the marginal cost is a point to be debated, but I would like to hear from anyone with knowledge of the law on this point and then see if a test case could be started.