There is a Bitcoin vending machine installed in Johannesburg at Mertroman. You can exchange your Bitcoin for ZAR at this machine.The use of Bitcoin by South African vendors is still very limited, and the idea for now is to educate merchants about Bitcoin. Is there in your country one ?
I live in a very foolish country where the lawmakers still believe counting currency notes with their hands is better than using online banking applications. So before the idea of Bitcoin will make any impact here, it might be after the next 20 years.
You think most lawmakers are foolish? Well guess what they definitely know what they're doing, whether we like it or not. Also note that pretty much every single country uses physical currency also, not only the country you're in.
And lastly, bitcoin is already making an impact. It's just that the impact is not 'that' substantial.