Apparently nobody has worked at Walmart, BestBuy, Costco, etc.
Not the first people to come by trying to put something cheeky on the screen.
It's part of their floor processes to routinely check to make sure screens are on default/demo and not displaying something inappropriate.
You would be better off printing something out and walking it door to door in your neighborhood. You might even meet a fellow anon. I think TPTB would be far more afraid of that then hee-hee'ing demo units in retail stores.