It weighs less. It didn't have to be as thick as plexiglass or other alternatives. It was stronger.
Well then why was it only used in aesthetically relevant sections of the piping and not the entire system? (Mind you, I'm not quibbling because I'm some Star Wars cultist or even convinced that all the 'science' in science fiction needs to be as realistic as possible. I'm quibbling because details like that were an extremely painful counterpoint to the good casting and generally good dialog in Abrams' Star Wreck.)
Cool news about the real zapped aluminium, but that pic only shows a transluscent substance, not a transparent one. Aerogels might be the more likely route to something super-strong and nearly invisible, maybe something like a diamond meringue.