Wait, so anyone can understand written English even if they don't speak English? So if I type in German you can understand it even if you don't speak German? Wie funktioniert das?
People can spell out words in a language they don't understand, as long as they understand the letters. This is good for names. People can only do this if they understand the letters.
They don't have to pronounce those: they can just spell out the letters: M-E-B-D. It's not that hard. But if the customer's name is "坂本", how exactly is the bank employee supposed to say that?