commercial banks dont accept bitcoin for now, They trade/transact in government backed fiat currencies only. Although Bitcoin is a legal payment tender in some countries. Your traditional banks do not directly deal with Bitcoin. There might be some intermediary who convert Bitcoin to local currency and vice versa. But with time i see a development towards this.
Well, that's right. Bitcoin is just for online business. Bitcoin is different from commercial banks because they really accept real money/fiats and not bitcoin. Bitcoin is just a digital currency, Banks need an actual money. Maybe they should accept it soon but not for now. Remittance centers are now accepting bitcoins. Here in the Philippines, there are some remittance centers that are ables you to withdraw your bitcoin through these remittance centers and it is nice to hear this. But, I hope that banks will do the same soon.