I am going to nit pic on language, as an educational and architectural wonk only, so I am not picking on anyone. This is a really common error.
Opaque means no light or vision gets through. The Airstream door glass is not opaque.
Obscure means light gets through, but not vision. This is what AS uses in the door glass.
Transparent means both light and vision gets through. Mostly we use this type of glass.
And of course you can have tinted transparent, which cuts down on light but does not obscure vision. So, what you want to know is why AS does not have tinted transparent door glass. All the rest of the door is metal, and metal is opaque. BTW, they do actually make Black Glass, that is opaque (no light and no vision) but has the exterior look of glass, that is a hard "glass like" look, and wears like glass. Mostly it is used in high rise buildings with all glass exteriors but where no light or vision are wanted.
Clear as mud now? Sorry I had to vent one of my little petty nit picks....LOL. Please forgive me, I feel better now.