Yes, and Apple also sold plastic laptops when they were still on Intel. Apple has repeatedly attempted to sell products with a cheaper chassis (iPhone 5C, Plastic Unibody Macbook) yet their customers preferred metal enclosures.

Yes, because they feel more premium, that's their "advantage". A headset which hurts your neck more in the long run could offset this premium feeling.

We don't really know why Apple chose Glass + Aluminum for their headset, but we do know for a fact that:

- 1 Their customers have historically chosen metal and aluminum for their products, and Apple is in the business of building what their consumers prefer.

- 2 Glass and Aluminum conduct heat better than plastic. The 2hr battery suggests thermals are a great consideration where the materials chosen were not just for aesthetics. Perhaps plastic could've worked, but see point #1.