"I wonder if the judge considers Firefox to be more than a program"
I'm sure the judge considers Firefox to be a trademark, since that's what it is. You don't get to use other people's trademarks to make your scam work. That's where the clever "grey area" of this scam turned into straight forward criminality.
Ask yourself: why did these users fill out all their billing details on the page presented? Was it because they thought it'd be cool to get billed for a lot of money by some company they'd never heard of? That doesn't seem likely does it. Well, what's on the page that makes them think providing their details is OK? There's the name Firefox in big letters. The users believed they were telling Mozilla (the people behind the Firefox brand) this information for some purpose. Free trial software often does this, Firefox isn't a free trial, but I bet my grandmother doesn't understand the difference. Using somebody else's brand to trick people in this way is illegal.