I hear ya, but like somebody else pointed out, other people could see it.
Plenty of other people saw this guy on the road. Why would some random people on the road be worse than some random people on the web? And if any family/employers see it after browsing through a pot forum, chances are they either already know or don't care. And assuming this dude has anyone who doesn't like him and decides to rat him out, then maybe he shouldn't have been driving with 100 pounds of hydroton on his scooter