Why are BD's & DVD's Region-coded?

[Roggster]

Region coding was introduced purely to piss me off

I cannot purchase Dave Matthews & Tim Reynolds Live at Radio City Blu-Ray because it is region locked to A.

Like I say, for no good reason other than to piss me off.
I'm pissed off about it.

Region coding pisses me off. Did I mention that?

I'd like to hear a good excuse/reason for region coding that makes sense (especially in this instance where no theatre release ever featured in the equation).
If it were for sound business reasons then the clever dicks who run all that nonsense wouldn't have plunged the world economy into recession.....

Oh, did I mention that I'm pissed off that I can't buy a blu-ray disk of one of my favourite artists because the dribbling idiots who make decisions about what gets released where and when don't think my money and devotion to their artist is good enough?