That would be amazing if I can use my bitcoins to pay for a piece of carrot. Well I think it's still far from happening in all countries, but I hear it is almost possible in Japan already. I wish I can visit japan today.
Spending or using bitcoin as to buy small things like piece of carrot will not be possible now as the transaction fees applied to per transaction in bitcoin is very high and small transaction like this will take you to a great loss. I think until the transaction fees of bitcoin are reduced or just canceled bitcoin cannot be use in places like super market to buy vegetables or daily good.
The fees are the main problem for every user and for every exchange. But I am hoping in future there will be stores around us which have a label as Bitcoins accepted. I will be a great this for me to watch.