We see a lot of fake Apple Watch silicone straps on the market these days for a fraction of the cost of Apple's Sport bands. Everyone's flocking to them and claiming what a ripoff Apple's are.
After having met with one of the best plastics watch factories in the industry who had the chance to work with Apple (they didn't in the end because the quantities were too high for their capacity...and Foxconn's 6 month payment terms were too onerous), they revealed a bit more information about the fluoroelastomer that Apple uses for the Sport bands, a material called FKM (fluorocarbon elastomer).
A couple of notable properties of FKM is flexibility and weight. It's going to be about twice the weight of silicone and just as flexible. It's substantially heavier than PU, which is also another common material for watch straps. This weight gives the straps a more luxurious feel and quality to it that cheap silicone just can't match.
The thing that shocked me, and I've been working in the watch industry doing product development for almost 2 decades now, was that on a raw materials' basis, FKM costs almost SEVEN times as much as silicone.
So the next time we jump to the conclusion that Apple's margins are exorbitant (and I'm not arguing that they make a lot of money off of us consumers), we can keep this example in mind and remember that they DO put a lot of attention into materials and details that we wouldn't normally know about.