Actually, if everyone spoke proper, precise English, we'd all communicate a whole lot easier and quicker, LESS people would sound like Morons, America wouldn't exist (what other purpose does it have other than to butcher the English language?).
People use slang not because it's easier, but because they don't know any better. Can't spell because? Then write cos. At least use an apostrophe. Unless you don't know what one is, or how to use one.
Of course typos can get into every post or sentence. I've probably boo-booed in this one. But the point is that speaking like a fool makes you appear a fool, makes your ideas harder to put across, and is bad manners to boot.
And by proper and precise English, I don't mean Shakespeare, and I'm aware languages evolve. But at any given moment there is a language that is prevalent and accepted - it is this that I am referring to.
Pick up an English textbook, and it is easy to follow. You might not get the jargon, but that is a separate topic within Language. You might not understand Automobile jargon, but that is not the fault of clear and proper English.