The problem is that money now is issued by governments. Governments are on average only governing one country, although sometimes more as with the Euro. In other words, it is not universal, so if you want to exchange some money for goods and services then you need to find the right money for the country the service is in.
Globalisation means we often want goods and services from other countries. But then we always need to find the right money for that country or use some de facto universal money like USD. But then you're always exchanging money or letting the US government (who control USD) exert some control over you, even though you could be outside the US buying a good/service from a non-US entity.
Bitcoin gives you a universal money. Once you have it, you can exchange it for goods or services without caring about where the recipient is. And you don't have to worry that you've now created a universal money that is controlled by one non-universal entity like the USA.
At least that is the idea
You already do that now. its called a job.
And then the coffee shop people give that money to their landlord, the power company, the coffee bean people, and also their employees.
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It seems like such bad faith arguments to claim that bitcoin doesn't have a use. It has an obvious use. HNers might not agree that it solves the problem it claims to solve, but if that's what you think then argue that. Don't pretend like you "don't understand" what the purpose is.
Bitcoin is a crypto CURRENCY. It IS money.
As far as governments have ruled in tax law, Bitcoin and other cryptocurrencies are not treated as foreign currency.
You don't need to complicate this further.
For instance: I am great at writing web APIs in golang, but unfortunately for me the people coming to my house today to deliver a dumpster (we're doing some spring cleaning) do not accept "golang apis" as a method of payment.
So I find somebody wants "golang APIs", agree to exchange with them for some money, and then use that money to pay the dumpster guys.
Money is a hugely innovative concept which has obviously driven a huge amount of innovation (now you can do work like "write golang APIs" instead of only doing things like "grow potatoes").
Does that help you understand what the point of bitcoin is?