The legal situation is more complicated than blaming the parents. To extend your analogy: If someone had a business that rented cars and somehow 11 year olds were renting the cars and driving them, the rental car company couldn’t shrug it off and blame the parents.

That’s why this is complicated: If a business knows criminal or dangerous activity is taking place on their platform, there is some obligation to make a good faith effort to address the situation. The expectation isn’t perfect enforcement because it’s not reasonable to shut every large business down as soon as 1 incident occurs, but if a platform becomes known as a haven for certain types of behavior then their liability continues to go up. Given how many people in this thread are joking about how Omegle was known as a free-for-all platform for people exposing themselves and as a platform for bored kids, it’s not surprising that the lawsuits are coming. Also, given their limited monetization options it’s not surprising that they choose to close rather than deal with legal battles.