Actually, I think it's a very good question.

[sarcasm mode on]
The great unwashed, unlike us superior beings, have only a superficial understanding of audio and fall prey to a few well-placed superlatives that focus on the little terminology thsy seem to grasp.

Witness the sales of Bose. Surely their sales do not depend on the seasoned audiophile (like us) but on the ignorant folks with more money and ego than knowledge of audio.

Likewise, "watts" is the end-all and be-all to many of those, although the lower income masses seem to be more succeptable. Notice that Bose never mentions these.
[/sarcasm mode off]

As far as watts go, there are watts and there are watts, and it all depends on how they are measured, and home theatre manufacturers aren't mandated by law to state how they are measured.

For instance, take an amp that's made for sale in the audio domain that measures 5 watts, 20 - 20khz +- .5 decible, at .05 percent distortion, with all channels driven.

Now, (and I'm guestimating here), if we were to measure that amp at 1,000 hz only, and extend the distortion to, say, 10%, and we only drive one channel at a time, then that amp may well measure in the neighborhood of 50 watts. Now, if we just measure a high-level input burst for just a millisecond, it may more than double this figure.

Maybe this link will explain it better : http://sound.westhost.com/power.htm