Forex is often subject to such taxes. If the USD and CAD were trading 1:1 then if I buy 1000 USD with 1000 CAD in cash I have right now, and then immediately b

Forex is often subject to such taxes. If the USD and CAD were trading 1:1 then if I buy 1000 USD with 1000 CAD in cash I have right now, and then immediately buy 1000 CAD worth of products with those USD, there are no taxes due. If I buy 1000 of USD with 1000 CAD, with the expectation CAD will fall, then since my taxes are due in CAD in my case, when I sell those USD for 1500 CAD I've realized a gain of 500 CAD that would be considered taxable income. But if CAD goes up and I have to sell those USD for only 500 CAD, then I've realized a loss of 500 CAD and I could deduct it on my taxes. Seems reasonable enough to tax currencies like investments when they're used as investments. Any asset held in that manner usually would be taxed like that.