There's a cost-benefit balance at play: is using the cost of the legal system (lawyers, evidence, courts, long tail on case times) better than developing a system to prevent fraudulent users?

I also wouldn't be surprised if there was a burden of "good faith effort" required to show that you've taken measures to prevent frauds.

There’s legal system that exist to deal with people stealing stuff from my house. But I still have doors, locks, cameras and alarm.