What magnifies the Bitcoin phenomena
is this is a worldwide market. trades 24 hours per day. The US is often not the largest trading market. As volatile as bitcoin is, it can be more desireable to hold than say the Venezualan currency. Its a way to get cash out of China and North Korea. (yes, officially banned, but it's not impossible to circumvent. Easier than carrying a sack of cash across a border)
The past week, though is purely futures related. No other crypto has budged.
Of course it will end badly. Of course it is in a speculative frenzy. But it's not that hard to understand that the finite number of Bitcoins dwarfs the number of people with the ability to trade them. Couple that with the ease with which Bitcoin (and all crypto) crosses boarders--that's not an insignificant quality.
It does have value, the same way way other third world country's currency has value. But right now, that third world's currency is rumored to replace the USD as world currency. You know how Rumors and pennystocks go.....never going to happen. But everyone thinks they'll get rich and get off the train before it collapses. It will collapse. But it will still have SOME remaining value at some point