You've been around this forum for a bit, so i'm sure this conversation happened more times than you can shake a stick at. But i''ll bite: You're talking about potential, not current, usefulness -- am i right? Because right now, if i don't need to gamble or buy from SR, my fiat does just fine, while Bitcoin ... well, i can't even gas up my car with it. As far as potential usefulness, I suggest you get behind my Bitcoin V2.0 -- I'll let you in on the ground floor & toss you a few coins.
Oh, and you can mine it while the difficulty's still low (sorry, old Bitcoin -- you had your day in the sun). My 2.0 is no different from bitcoin, other than lower total coin count (+1 for RARITY), so it's potential usefulness is no different from Bitcoin V1.0.
So, is it rarity & usefulness that gives Bitcoin value, or could it be ... something else?
Last week I ran a poetry contest. The entries came from all over the world (I can only assume, I did not actually ask where anybody was from). At the end of the contest I was able to send a little bit of money to about ten different people I had never met before and all I had to identify them was a single string of characters, the money was sent instantly for an a "generous" fee of the equivalent of 0.1 USD. You don't see how bitcoins are useful? Maybe I could have sent them cash in the mail ... 0.41 usd
each for the postage, but wait I don't have addresses for them, I could ask for their mailing address, but no, they would not want to give me (an anonymous guy on the internet) that information, so my giveaway would have failed.
My immediate question is: What in the world will those people do with Bitcoin?
I know decent God-fearin' American patriots would rather burn the American flag than take part in a poetry contest, but you must have had some real live Al-Qaeda type international terrorists! I mean, all of these people had Bitcoin addys & used Bitcoin already? And they lived all around the world? You're pulling my leg! Not a single one of them waxed poetically "[TL;DR] WTF is Bitcoin"? Amazing.
But let's assume these folks had Bitcoin wallets & knew how to use them ( having texted "BRB, wallet synching" to their respective muses, putting poesy distillation on hold), where in the world will they spend those tips?!