If there is price fixing collusion between the banks...I imagine you have some sort of watchdog government regulatory branch?
Yep - or the debit fee wouldn't have been reduced to retailers [who are going to drop prices in return, right? Uh huh....] but you see what happens when they take action: the banks [and every other 'regulated' industry] simply find new ways to return the profit they lost - and they're better at finding than the regulatory agencies are, absolutely.
BTW..If you think the fees are bad here...you should have had to deal with Canadian banking system....It felt like they had a fee for processing a fee....
American banks [and phone companies, rental car agencies, airlines, hotels, etc] do it too - read the fine print on the statements.