Soundstage - Too much?

I found the sound stage is very dependence on the recording or mastering process. If you have Roger Water's "Amused to Death" or "Casino Royale" then you have have sound stage beyong the speakers. With "Amused to Death" you'll actually get 180 degree surround sound effect. It's pretty cool. However, in classical music, I have yet to find a recording that will project the sound stage beyond the speakers in a convincing matter. If you know of one, please let me know.

Copland 100 on Reference Rec. "Fanfare for the common man" the entire hall is there, front, sides and around. I think alot of the RR recordings extend the stage.

Could someone explain how it is possible for the soundstage to extend beyond the side walls? Is this an aural illusion? Staying in a flat I wouldn't like to think my next door neighbours were getting some of my soundstage,would seem a waste to me.

For those of you who answered the questions, thank you.

Inspite of knowing that there is no such thing as soundstage depth (but certainly left to right imaging spread) that real live music (for small group, jazz or quartet ), the effect certainly is desirable.It just seem that we are getting our money's worth. For a live Classical Orchestra there certainly is depth in real life, albeit not as deep as some systems manage, it is pleasant to have it all the same. Although on some recordings the pitch definition could be not as clear as what you would like. That is the cost of having unnatural, but desirable, soundstage. Even My Dunlavy V's manage extra-wide soundstage beyond sidewalls on certain recordings(buena vista social club for example), but it is rare in my case.