Even if you close-miked the performers individually and mixed the signals yourself, you would still hear a surprising amount of crowd noise--and then you'd have to add ambience and reverb yourself, or the result would be unlistenable.
When you record from a "semi-distant" position as with all two-mike stereo techniques, for better or worse you get about as much sound from the room as you get from the performers, if not more so (especially in small and/or dry rooms). If the jerks^H^H^H^H^H customers who make the band's performance an economic possibility are talking their fools heads off while drinking and trying to get well laid that night, that's a lot of what you'll pick up.
I think some of the perplexity may come from imagining that "hypercardioid" is a narrow pickup pattern. A cardioid is basically an omni with cancellation in the back--a rather broad pattern; "unidirectional" is a marketing term which completely misrepresents the situation. A hypercardioid is only somewhat less broad than a cardioid plus it has a small but significant rear lobe. Microphone patterns--even those of long-barrel shotgun microphones--are never like flashlights.
On top of all that, your hypercardioid is more of a supercardioid no matter what AKG calls it--but if it were a real hypercardioid it would actually pick up more sound, not less, from the back, so be glad.
--best regards