(On the other hand, if large companies will accept it in payment, they've probably got an idea that a given currency will be around next month or next year.)
I don't think this is the most likely answer. Most likely is that the big companies have an instant exchange set up where a purchase made in bitcoins is immediately converted to dollars, and they charge their customers a small transaction fee in the form of an exchange rate difference.
It's not a given that low voter turnout is a problem. We don't need more low-information voters (89% agree that DHMO should be banned) and we don't need to coerce those who do not vote to signal their non-consent to the system.
Amen.
Anyone can make an omelet with eggs. The trick is to make one with none.