The only thing you cannot do with bitcoin is pay taxes directly. You can do that indirectly by trading your bitcoin for USD. There are a lot of different goods you can buy with bitcoin, some of which you cannot buy any other way (many are illegal but that is a different matter). Bitcoin is traded for other currency all the time.
I tend to believe those who say bitcoin will not last are right, but right not it is a currency. Not the most useful one, but there are countries with a real currency that is not very useful.
That's like saying I can pay my taxes in barrels of oil, I just have to sell them first so that I can pay in my government's currency.
Like, what accountant would be capable of planning finances for a business where every single liability is denominated in a super-volatile asset? The whole thing is nuts.
People rarely do this. However a lot of accountants do this.
Nearly all large and even mid sized companies have customers who use a different currency and have to deal with it. Big companies hedge foreign currency risks. It is common for the press release for a companie's earning to say "we made $x per share driven in part by foreign currency values and ..." Which is to say when looking at a press release they believe their investors (perhaps a legal requirement?) will want to know that a significant factor wasn't sales but just currency trade.
Now bitcoin is super-volatile. That isn't relevant to a general discussion, but it is a major factor when discussing bitcoin in specifics. There are other foreign currencies that have similar considerations at times though, it isn't unique to bitcoin.
Euhm, almost every single country on the planet ? (granted, one or two exceptions)
Even the value of the dollar is significantly in the social contract with Saudi Arabia (not sure if "social" is the right word, but it's definitely not legal, as both sides are sovereign and thus free to change any law or contract between them)
Seems to work well, for the most part. Granted, on occasion disasters happen.
I tend to believe those who say bitcoin will not last are right, but right not it is a currency. Not the most useful one, but there are countries with a real currency that is not very useful.