I'm not aware of any similar arguments being tested in court, so this is all conjecture.
That said, barring an explicit definition of 'Internet service' in your service contract, it's commonly understood that requesting a page from example.com, all the data your ISP returns implicitly is sourced from example.com. Introducing your own content in between is therefore fraud, as you've mis-represented the origin of the content.
I believe the owner of an involved web server would have standing as well, not just the users.
That said, barring an explicit definition of 'Internet service' in your service contract, it's commonly understood that requesting a page from example.com, all the data your ISP returns implicitly is sourced from example.com. Introducing your own content in between is therefore fraud, as you've mis-represented the origin of the content.
I believe the owner of an involved web server would have standing as well, not just the users.