What would likely happen if you decided to bring out this Penthouse at work. Just reading it would probably get you fired. Exposing it to co-workers would bring on sexual harassment charges.
Doing the same on a park bench, city bus/subway, etc. would likely get you in trouble as well.
Why oh why can anyone defend this behavior in an even more confined public space, such as an airplane?
And, yes, I was in Florence recently as well, (and yes, I find such art enjoyable). The comparison of what is there to a Penthouse is ludicrous.