If you can't communicate over distance by shouting and not being rude, that is an issue you have. The rest of us can do it perfectly easily.
If I'm standing in public and someone starts shouting at me from a distance, when there is no apparent reason why they can't simply walk over to me, I'm hardly likely to think "What a polite and reasonable person. I'm going to pay them full attention and address their concerns".
Normal people shout when there is no alternative, or if there's some sort of safety issue. Normal people don't resolve conflicts by shouting.