> There are only two methods of exchanging goods
I don't agree, it's always barter ("I'll give you something, if you give me something"), the only difference is the goods exchanged.
Paying in sheep doesn't work very well in most cases, sheep require too big a wallet and are too big a unit for small transactions (a cup of coffee or a bus ticket).
So people decided to use something with an intrinsic value as some sort of proxy, or abstraction layer, and invented money. Precious metals were perfect for this, they are easily divisible and have an universal intrinsic value which made that you felt comfortable exchanging your ware for them: The amount of precious metal you got in exchange was indeed worth just as much as your wares.
But then came the clever ones, and said "Never mind getting anything for your valuables, just trust us". And because people are
stupid trusting, it worked. That started around the World Wars, with the end of the gold-convertibility of currency: Before that, your dollar was worth real solid gold, and its value was thus stable, the paper bank note being a proxy for something real; Now your dollar is only worth the trust you put into the US government (or the trust the US government can bully out of you)...
Of course governments like this new system, it allows them to print as much money as they want, any time they want, and of course ordinary people don't like it since it means their meager savings are as many cookie jars governments can loot at will. But it's all in the name of progress, isn't it.
And to get back on topic, here come the big corporations and say "Hey! We want to print money too! Trust us, we're big and powerful." Except that in Facebook's case nobody trusted it. Not only wasn't it trustworthy enough, there also was no real incentive for the already established actors to scratch Facebook's back.