I redeemed Scene points for a Disney gift card last year and yes it works the same as a physical one in the US. I just took a screen shot of it and showed the cashier when making a purchase and they scanned the barcode on it. Of course its in Canadian funds so the first time I used it, it was converted into US at the exchange rate for that day. The remaining balance was is US. It was fun to have "free" money to use at Disney but the exchange rate was a bit painful. Last fall a $25 Canadian GC gave me about $16 with exchange.
Someone on here suggested using the points for groceries then purchasing a GC at the store instead of redeeming on the app because you get more bang for your points so that is also an option.