You haven't seen "Olympia", then. Or "Dejeuner sur L'Herbe", among others that caused a morality ruckus in their time. They're classics NOW, but they weren't born that way.
Be that as it may, very little art, nude or not, was created for the sole purpose of inspiring male mastubatory fantasies.
I am sure the creators of those pieces viewed them as fine art and the execution of artistic expression.