Parental controls to restrict in-game purchases
In-game stores in Hearthstone and World of Warcraft have left Blizzard's parental controls with some catching up to do in order to keep youngsters from accidentally racking up credit card bills. As of now, parental controls will prevent in-game purchases in Diablo, Hearthstone, and WoW by default.
If you don't use parental controls, but want to start, just log on to your Battle.net account and go to Settings > Parental Controls to be walked through the setup. If you use parental controls but don't want to block in-game purchases, you can turn them on by following these steps:
Log in to Battle.net and visit the Retrieve Parental Controls page.
Enter your Parental Controls email address.
Click the Send Parental Controls Email button.
Check your Parental Controls email for a message from Blizzard Entertainment.
Click the link under the account user's name. This will take you to the Parental Controls setup page.
Under the Purchase Settings section, check Allow in-game purchases, and click the Save Settings button.
For more details on parental controls, check out the parental controls FAQ.