Even though it's easy to fix, having this as a default is the problem. I wonder what it would take to really make Network Solutions feel the pain for this kind of malpractice.
There's nothing I should have to "fix". If I own a domain, then own all the subdomains. It's not some open public space for someone to grab for advertising.
Not sure I see an issue here. It's something you can fix yourself in like 5 minutes.