A. The name doesn't imply anything. Sunglasses aren't always made of glass. They're also called spectacles and eye wear. When someone ask for a glass of water you don't need to literally give him a glass of water. A plastic mug would be absolutely normal.
B. Fashion accessories are worn for attention. That's the whole point. Why wear a belt if your pants are falling off? Why wear ear rings which have no functional purpose?
And don't worry about downvotes. You're not on the opposition like me. I've been constantly downvoted despite giving very valid reasons and still no one has answered my question. Looks like I'm surrounded by people who hate others for nothing :(

So following that line of logic, people can't wear wigs, get dentures, wear colored contact lens, dye hair, wear a watch for accessory, wear a scarf on a hot day, wear perfume, wear a cap indoors, or a uniform outside work because they're posing?
As far as I see it, getting people to wear it for fashion has several benefits:
1. Decrease stigma about wearing glasses. Which would lead to less bullying.
2. Decrease price by increasing market size and competition (economics).
3. Motivate manufacturers to create better designed glasses due to increased demands.
4. More fashion accessories, especially for guys.
And you didn't provide me any examples of how this negatively affects other people.

It's only creepy if you don't do step 1 & 2

I think you're viewing it on the all page, which currently shows posts from everywhere. http://funsubstance.com/fun/126303/introducing-substance/?last_comment=544008#comment544008