...compared to say u.s. dollar bills which you can hold in your hand or stuff in your mattress.
this is why bitcoins will not go mainstream because majority of human beings on this planet do not have access to a computer.
Where did you get that information about 60% of people dont have access to a computer? Maybe in the old years yes but now I think most of the people have a knowledge and can have an access to a computer, aside from that we have android phones now in which you can access your balance in a second and make a BTC transaction.