This just gets better and better. Probably been asked before, but why is it in general that girls are not as enthralled by HT/Music systems as guys? Neither in the home nor in the car. Even the girl engineers I worked with didn't care much about it. In addition to high quality, I especially don't understand their lack of interest in bass. It seems the low frequencies might... well, nevermind.
For the answer to your question, one would need a proper survey of many people. But I thought I would share about one woman in particular. My wife enjoys our audio gear very much. She likes the subwoofers (we have a pair of
SVS CS-Ultra subwoofers). When I got them (I did not ask her first), she questioned the need for them (we previously were using a Carver Cinema 5.1 subwoofer). She did not want extra, boomy bass (this ties in well with what
Alex2507 says above). However, I explained to her that it was primarily for greater depth of bass, though it would also be capable of extra output. I set them up to give me a flat frequency response (as flat as the room allows, of course), not to exaggerate the bass. She likes them, and enjoys them. However, if I were to distort the sound by having exaggerated bass, she would not like them. She wants it to sound good, not screwed up the way that many men like.
For the main speakers, again, she enjoys what we have. She is not interested in any of this stuff qua equipment; she is only interested in the results. If we had piles of gear that did nothing, she would not like it. If I wasted money on magic wires and other BS, she would object to the money being wasted. But I never spend what we cannot afford, and I only spend money when I get actual performance from it.
When she watches a movie, she wants it to look and sound good. How that is done is of no interest to her.
Another thing worth relating. She asked me about the need for such big speakers, and asked about the "cute" Bose speakers. I explained to her why they would not be satisfactory, and that was essentially the end of it, as I do not tell her BS stories the way that some men do with their wives (which, of course, gives them good reason to disbelieve their husbands).
But there is nothing like a fact learned from one's own experience. One day, we went to an acquaintance's house for a party, and they had a room full of Bose cube speakers that were playing music while we were there. After we got home, without any prompting from me, she commented on how bad they sounded. Now she would not want Bose cubes even if I wanted them. She does care about the sound, and would like it to be as unobtrusive as possible. But she does want good sound.
If I were incompetent in setting up our gear, then she very likely would not like the results, and would question the need for it. This, too, is a factor in the whole thing. When someone sets up expensive gear improperly, another person is quite right to question the need for the expensive gear. After all, if one gets bad results, what was the point of it?