People act like the world wasn't always hilariously twisted. Before religion was invented, people used to walk into town wanting to marry a goat. It wasn't until people waved a book at them and told them that was wrong they stopped. Remember, when you're in the hot desert with no air conditioning, no electricity, and no internet, idle hands WILL do the devil's work as the old saying goes.
And the Romans? Ever heard of public orgies?
If anything, human beings today are way more restrained and curbed by societal norms.
Now...
Cue the sexy party!