Why do we pay taxes when spending Bitcoin?

Have you ever wondered why using Bitcoin to purchase something, like coffee, is considered a taxable event? In Canada, it incurs capital gains tax, while regular currency does not cause such issues. If Bitcoin is indeed money, then why can't it be taxed like regular money? Is this just a temporary difficulty until tax legislation adapts? Or is it the price to pay for having money that is not subject to government manipulation?

Fact: In some countries, Bitcoin and other cryptocurrencies are considered commodities, which leads to taxation when they are used.

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