When I was a kid, movie theatres tended to have the screens fairly high and the seats were all at or near ground level (very gentle slope), meaning we all looked up at the screen. Over time people apparently concluded that this was bad, as stadium seating and higher seating elevations (relative to the screen) have become the norm in the theatres I've been in. Now it's much easier to look straight ahead at the screen.
Why, then, when LCD and plasma TVs give us the ability to mount the screen on a wall instead of putting it on a stand, do so many people mount it at or above eye level while standing? This means that if you sit to watch TV (which most of us do), you're looking up at the screen. I'm talking about people's homes, e.g. above the fireplace in the living room, not restaurants where other considerations might apply (like battles for control or risk of damage from patrons).
Are people being driven by a sense of what's aesthetic on walls (we're used to hanging pictures, mirrors, etc higher)? Is there some user-experience reason that it's better to look up when watching TV? If the latter, why doesn't it apply to movie theatres?