the average person really does not need that much protein in their diet.
personally I think protein shakes and powders are an unnecessary fad. if you are eating a diet where you aren't starving, e.g. you're getting 3 meals and you're not suffering from malnutrition, you're probably getting enough protein (unless you eat all foods devoid of protein). one piece of meat, eg. chicken or fish, should get you enough protein.
any excess protein doesn't have any added value to body-building. most likely, it will be converted into something else; or you'll piss it away. (I have to verify the facts on that. i remember my friend telling me that.)
Jack Burton: I don't get this at all. I thought Lo Pan...
Lo Pan: Shut up, Mr. Burton! You are not brought upon this world to get it!