"What's up" - It's not Cool

Too many cliches in our daily conversation. While I don't have any problem with "How are you" and "How is life", which are supposed to be conversation starters and people having acknowledged these with no disregard, I have a problem with "What's up". This is so commonly used now a days and with no real intent that I can't refrain myself from calling it - The lazy man's resort. If you disagree, search for "whats up" in your GTalk chat history and the results are there for you to see. It has become so so so common that you feel like you are missing something if you haven't asked what's up to somebody when you meet him/her.

I have 2 problems with this question.

One, when you know the person whom you have asked this wonderful (supposedly 'Cool') question, is going to say 'Nothing', why do you have to ask such a question in the first place? In fact, with a great degree of certainty, I can say that 'Nothing' is the most common response. 99% of people say that.

Two, when you have simple words like "Hello" and "Hi", which are less irritating and more polite (less 'Cool' though), why on Earth would you want to use "What's up"? If you are greeting somebody just for the sake of it, wouldn't one of these two simple words do?

For full effect, "What's up" is best delivered while walking past someone at about 90 m.p.h. so the person you're talking to has no time to respond, and in a tone that suggests you really don't give a shit about "what's up" with them.
Dude 1: "Hey man, What's up?"
Dude 2: "Ah..." (what he managed to get out before Dude 1 was already too far away to hear the rest of what he was going to say)

Some smart people answer it by responding to "What's up" by saying "The sky" or "da roof" (which was actually intended to make fun of the question). In spite of this, these bunch of "What's up" guys never seem to give up their habit of asking the most famous useless question. I wonder why people always ask each other the same question over and over again. Are we really that dull?

I'm just so irritated with this extremely overused question that the next time someone asks me "What's up?", I'll say "Nothing. If you ask me again I'll roast you"