There are a lot of ways for them to monitor their children's internet activity. They should really utilize those if they wanted to take care of their children. Also, they can just increase their children's literacy when it comes to finance.
That's what I do. I buy an annual subscription to the 'Kaspersky Safe Kids' program, which can be installed on any number of computers, phones and tablets. This program has huge possibilities.
Disclaimer. I am not publishing its name for advertising purposes. It may help some parents to control their children.