I believe the answer to your question would be when the big supermarkets accept some form of btc for their goods.
well it could be right , i think bitcoin would never be convenience for transactiom cause the volatile of the price but still there a way like using pundi x project that helping people and merchant to accept transaction using cryptocurrency.
in my opinion if that person can use or make a lot of money from investing. and can meet the family's economic needs. and can shop with bitcoin. and bitcoin is recognized by the state as a valid currency
Bitcoin users will be comfortable if they will get benefit from using bitcoin, it is very easy because of its worldwide recognition, if we go to shop and we ask for payment using bitcoin, I am sure there will be no hurdles, now a day price is also being high because of popularity and acceptance of bitcoin, we can use travel using bitcoin as air travelling accepts bitcoin and all markets are having bitcoin system now so it is very comfortable for all of us,