I'm with Wayne. My largest amps are 45 watts per channel. I can send you out of the room with them and the speakers are only 92 dbw. I see very little point in anything over about 200 watts per channel. My opinion is that this is a not so subtle "horsepower" war and marketing ploy to get you to spend more money.
I see your point gofar. If we are talking about 200 watts per channel, then that means the whole system can be at least, 600 watts. It is true that all these are marketing gimmicks that consumers (so easily) fall for.