Public nudity is an issue of politeness and convention. I generally spend most of my summer wearing only shorts, sneakers, and a baseball cap. It's a great pleasure to feel the sun and a warm breeze on your chest after six months of being bundled-up like an Eskimo. I'm sorry that women are not so generally granted this same pleasure.
However, I know when I should put on a shirt, and when I should put on a jacket, dress-shirt and tie. I certainly wouldn't walk through the village without a shirt. Still, I suppose a certain percentage of people I pass while rollerblading or hiking, are offended at the sight of my half-naked torso.
BTW, my brother Tom told me a funny story about his trip to Athens, Greece years ago. He and his buddy checked into a wicked cheap backpackers's hostel (The Hotel California). The guy at the desk told them about the bathroom down the hall. "No, problem," says my brother, "we didn't expect the bath to be en-suite." So, he and David stashed their packs in the dorm and headed to the shower with their towels. However, when they walked into the large open room contining toilets and shower fixtures, they were shocked to find a woman lathering up. They hastily retreated to the hall. David ran back down to the guy at the desk only to be told that yes, there was only one shower. David ran back to Tom with a big smile on his face. For all the time they spent in the shower during their visit to Athens, I suspect a good deal of ancient ruins went unseen. However, Tom said that when he had to use the toilet in a less superficial way, he waited until 2AM. As much as an 18 year-old guy enjoys showering with women, it's another thing entirely to sit on a toilet next to one.
Lastly, I remember a quote from either Steven Pinker's,
How The Mind Works, or Matt Ridley's,
The Red Queen, "In general, a man sees a naked woman as an invitation, whereas, a woman sees a naked man as a threat."
Michael