The only explanation I can come up with is that they are targeting the people who are ripping the DVDs for distribution. So 5 people on the whole world. Sounds reasonable :/
Ah, those who are already aware of, and unconcerned by, the warning.
And I would doubt that anyone who's ripping professionally is unaware of the (potential) legal consequences, should they get caught.
I recall hearing that it's to try to make piracy be seen as less socially acceptable.
It's working for guns, might as well try the same for DVDs.