Lets just accept the truth that as long as the governments are not endorsing bitcoin as a currency, we will be at the same situation for a little longer, until the people are the one who are already spreading the news about bitcoin and forced the government to just legalize the use of it.
Though I don't see the time that bitcoin will make banks disappear, I think it is possible that bitcoin will be seen on banks...

Bitcoin doesn't offer the average joes what they want in order to fully adapt it at some point. Here are some reasons;
# Bitcoin isn't a suitable currency for daily purchases due the fees that are likely only to increase, and of course don't forget the confirmation times.
[1]# Bitcoin at all times requires you to be connected to the internet.
[2]# Bitcoin is subject to the volatility.
[3]# Bitcoin can't handle mass adoption.
[4]# Bitcoin is a decentralized incentive, which the average joe type of people don't feel comfortable with as they are used to have the government as central authority.
[5]# Bitcoin is too complicated for a lot people.
[6]# Bitcoin has almost zero merchant adoption if you put it against how other payment services are being accepted globally.
And there are probably a few more things... Long story short; Bitcoin is just an asset as Gold, but then with a far better usability. Gold 2.0?
[1] Not necessary "all the time" but only when you're sending money or when you're checking if you already received the payment. Even after being offline for a couple of weeks, your bitcoins would still be in your wallet.
[2] It's a disadvantage to the average joe but it's an advantage to most of us. Eventually, the average joe will evolve and learn how to take advantage with the price volatility.
[3] Maybe not now.
[4] Sadly but people always want to have someone in charge even in small activities (i.e. group activity in school) which obviously don't call for an authority. Maybe the average joe would want to try something new and try decentralized stuffs.
[5] Only when you're not a tech savvy and if you don't read much. You don't have to be all technical.
[6] Eventually, we'll get there although it might be much longer than we are expecting.