I do not think bitcoin being known worldwide can make banks disappear unless bitcoin will going to have a much stronger security when it comes to  saving coins in wallet. or maybe someday and we all wish that bitcoin is going to be more useful when buying some important stuff and some basic needs in our daily lives .. we may never know what future may give us  but let us all just hope for the best both bitcoin and banks too..because this two (2) have giving us all benefits in saving and investing for  our future..