Why don't more recordings have soundstage outside of speakers

Mahgister, I want to limit this discussion to live recordings only. Studio recordings are all bets off. But, with live recordings one would like to be able to appreciate the acoustics of the venue the music was recorded in. Those acoustics are imbedded in the recording sonically but unless you have a very elaborate multi-speaker system you can not replicate the directionality of the reflections that clue you into the acoustics. You have to depend on your room to reflect the reflections from the rear where they came from originally. Your room becomes an integral component to your system. This is why a totally dead room sounds "wrong." It is sort of like the applause in a live recording is wrong because it is all coming from the front and not all around you. The distinction comes in the timing. Very early reflections could not be construed as acoustics from the original venue. They come to early and they are loud. They ruin detail and imaging. You want to turn them of to the greatest extent possible but allow surfaces farthest away from the speakers to remain reflective. 

As others probably have already said, if the ambient cues aren't on the recording, you won't hear it in your room.

In my opinion, the only way to get a natural soundstage that extends beyond the edges of the speakers, is to record a live event, with care taken to capture the venue ambience. Soundboard recordings are unlikely to do this.

There are studio recordings that use panning, phase and other 'tricks' to get sounds to come from beyond the speakers, but those types of techniques come off (to me) as a bit gimmicky. 

Classical recordings, where the soundstage extends past the outside edges of the speakers, are almost a given, not the exception. At least as far as I've been able to discern. 

But I consistently get soundstages that extend well beyond the outside edges of my speaker (and very deep, too). The illusion of instruments coming from 4 meters beyond the outer edges of my speakers, is not unusual. I've had my dog go running out of my room, growling at the violin that she thinks is coming from down the hall. 

There's actually a very prosaic answer to this question. When we listen closely we tend to look in that direction. Ears on each side of the head, duh. When we record we do the same. Maybe there are groups the performers occupy different locations around the room at random. Not many, is my guess. From intimate solo singer to full orchestra to U2 extravaganza the performance always occupies a relatively small area in front of us. 

Anything way off to the sides is therefore much more a gimmick or effect than music.   

There. Done. And on to the next question. ....  

duh?

@simonmoon, I certainly agree about the gimmicks however I have learned that instruments themselves should not come from beyond the speakers which is what you would expect if you think about it. I use to occasionally hear some instruments on certain recordings come from beyond the speakers. I have been using dipoles exclusively for 40 years and I use to never put any sound absorption behind the speakers and I always put my speakers near corners. So, sound would bounce off the front wall then off the side wall to the listening position. It is no surprise then that sounds would appear to come from beyond the speakers. Back then I felt the sound had more "air" to it that way and I really did not appreciate what it was doing to the image. I now use 4" acoustic tile behind the speakers and at first things did sound more closed in on a relative basis but the specificity of the image increased very noticeably.
Now only gimmicks come from beyond the speakers but, now close your eyes and the speakers disappear. Even instruments that are panned hard left or right do not appear to be coming from the loudspeakers, they just hang in space. You could walk around them (if you could walk through walls).  
My intent is not to brag but to help others achieve the same results. No system images well out of the box, it is a virtual impossibility and that goes for my system also. You get the standard 2 dimensional blurry image that most of us think is the cats meow, until you hear a system that really images. I have been talking about the need to synchronize the frequency response of the main speakers for years. That need became even more obvious with the Sound Labs speakers as they are capable of a better image than my old Acoustats. This synchronization and control of the room's acoustics are the two most important considerations if you want your system to image at it's best. I am convinced that this applies to regular dynamic loudspeakers also and not just to big dipoles. I hope to prove this to myself with my friend's new S7s.