demand what?

"Think about why firewalls succeded in the marketplace. It's not because they're effective; most firewalls are configured so poorly that they're barely effective, and there are many more security products that have never seen widespread deployment (such as e-mail encryption). Firewalls are ubiquitous because corporate auditors started demanding them. This changed the cost equation for business. The cost of adding a firewall was expense and user annoyance, but the cost of not having a firewall was failing an audit. And even worse, a company without a firewall could be accused of not following industry best practices in a lawsuit. The result: everyone has firewalls all over the network, whether they do an actual good or not.