Neither blocking sites nor their financial transactions would stem the flow of illegal online gambling operators in Australia.

That was the point of the Digital Industry Group Association—whose members include Facebook, Google, Twitter, Microsoft and Yahoo—in its submission to the Barry O’Farrell-led review of Australian online betting laws.

The focus of the review is whether tougher measures to deal with international gambling sites could keep Aussie punters from using them. However, social media and web companies just don’t buy it.

“We consider there to be fundamental flaws and significant practical difficulties with any attempts to filter the Internet such that it may not be possible to automatically block content,” the group said in a submission. “Who would determine whether a service is illegal and would entire websites be blocked if there are both legal and illegal services on the website?”