[freehunter]

You can argue it's abuse or illegal or fraud or whatever you want, but here's the thing: how are you going to stop them? Sure, maybe you stop Facebook with a lawsuit... but everyone else is still doing it, even people outside of your legal jurisdiction. They're still going to do it, so it's up to you to stop them with your design. If someone breaks into your website and destroys a user's data or steals their credit card, that user is not going to want to hear "but what they did was against our ToS!"

This isn't your house where there are police patrolling and ready to respond at a moment's notice when they're called. This is the Internet, accessible by almost literally everyone on the planet, and they don't give a shit about your policy. That's why best practices and application security was invented. So use it.