OK, this doesn't even seem to be English. You sound disoriented, bro. Please make sense.
I said Batman uses a different voice, you said "No! Bruce Wayne uses a different voice!" LOL, ok.
The bottom line being that Wayne and Batman use 2 separate voices to assist in masking their identity. Since Wayne is in a position where he talks to press, speaks at fundraisers, etc. - a lot of people are familiar with his voice, it makes sense to conceal it as Batman, which is why Bale's raspy interpretation makes perfect sense. This conversation makes typical semantics arguments look like Plato's Symposium.
I don't understand why this is so hard for you, bro. Help me to help you.