I think it has a value because people understand it, we can see how the engine was made and since it is a fair deal for all then people decide it has a value. The value is variable because is based on a market, but what we know is the value will never be zero.
I don't think so. I'm pretty sure that people who actually understand Bitcoin is only a small minority. All they need to know is that Bitcoin is decentralized, trust-less, unconfiscatable, and has a hard limit. I think knowing those characteristics alone will be enough for the typical non tech-savvy person to know that it's worth something.