It's a combination of lazyness and, no matter what the accused might say, a lack of care about their language.
You must realise that with mobile phones, email, and all the other popular electronic communication systems the ability to communicate effectively has taken a SERIOUS turn for the worse, and I'm sure it's not just English.
Every time I see people type 'liek dis n say stuf dat anoys mi rly gts n mi nurvs' I really do feel sad.
I, rightly or wrongly, take great pride in my ability to speak clearly (alcohol not withstanding), type properly, spell properly, ennunciate properly and behave in a manner (publically) that befits my surroundings. I always start emails to people I don't know with "Dear Sir" (or equivalent) and NEVER hi, and I always end them with "Regards" (or equivalent), never "cheers mate". Why don't people bother? Are they too lazy? It doesn't take a second to be polite and it costs nothing. Are they too stupid? Possibly. Probably even. But why are they content with either BEING stupid or appearing stupid?
I have a contact on MSN (from the LFS world, but not a regular forum user afaik) who added me recently. He's CONSTANTLY rude, abuses people's name (he was calling Darkone D
orkone to his face), swears all the time, can't spell, appears to have little or no ability to think for himself, dislikes reading (probably a result of lack of intelligence), and yet would almost be first to shout "we are all born equal". It would take him virtually no time at all to think about what he types or says or write. Sure it might take time for him to learn to spell simple words, but nothing that couldn't be achieved. He could read - he won't even read short tutorials on how to do something but expects me to take my time to teach him step-by-step. It's flattering in a way, but annoying in so many more. His excuse is he has a problem that he's rude to people, and can't help it. Well, thats rubbish. EVERYONE can help being rude. (and if you read this 'mate', consider it payback for what you say to me on MSN. This isn't uncontrolled rudeness, it's rational rudeness, a much meaner thing
)
I don't know whats causing it. The decline of the educational establishment can be traced to many causes. Lack of disipline, lack of good teachers, too much priority but on finances within schools (i.e. run to make money, not the teach people).
But you're right, and it does upset me.