Loud cellphones in Public

Am I the only one who gets irritated when people have their cell's volume up full blast? I'm not talking about the ringer, I'm talking about all the other things. 
It is NOT necessary to have the game sound effects up full volume when you're sitting the the dr waiting room.
I shouldn't hear BOTH sides of the conversation from across the room if you're on a phone call. 
And why the hell do people walk around the store holding their phone up to their mouth with their phone on speaker??!