There are not that many banks out there that accepts bitcoin, when bitcoin is their direct competitor especially on international transfers. However, a lot of banks are actually looking into using blockchain technology to create an immutable database of transactions.
In my country if they find out you are buying bitcoin via bank transfer they might actually freeze the seller's account.
Not even a single bank i find out in my city and country. If bank accepts bitcoin means then we could make interest also with the bitcoin saving. This is a only disadvantage in btc then this will also rectify by that.