It's not telling you anything I'm sure you haven't already figured out, but I suppose you'll just have to play it by ear.
It seems extremely unlikely that a community theatre group of a size and level of competence necessary to tackle a large-scale musical would genuinely attempt to do so without any stage management support whatsoever. Some possible explanations...
Good reasons:
- They're a thoroughly collaborative company. (The creatives make collective decisions, the right hand always knows what the left hand is doing, etc.)
- The director doesn't like using stage managers, and prefers to work within her own head. She'll be taking her own notes, tracking her own blocking, etc.
- The company is super-organized and has a structure such that many of the normal SM administrative duties will be handled by back-office staff, volunteers, or company members, with the the expectation that the non-administrative stuff will be picked up by the production departments and technical director.
- Everything is real simple and loosey-goosey, more akin to a village pantomime than a serious take on a musical. (A SM presence might still be desirable--but it might also not be, insofar as you might want the chaos at the backend to filter through to some extent, if that's the aesthetic you're going for.)
- There was so much interest in the SM job that the company wound up splitting it into smaller chunks in order to appease the volunteers.
- Another job (likely Producer, Production Manager, Technical Director, Assistant Director, Company Manager, or something else in that line) has historically done what we would otherwise expect a stage manager to do.
Bad reasons:
- The former stage manager (who had the gig for 40 years running and practically came with the building) has departed and something (collision of egos, lack of interest, lack of qualified people, lack of attention paid to this person's absence, etc.) has prevented a new one from being found in time.
- The director is unqualified: he has never worked a show on this scale, is more used to teeny-tiny shows with teeny-tiny casts, and when asked "do we need to find you a stage manager?", he figured he could just squeak by because he'd always done so previously...
- The company is over-ambitious and is either too small to attract enough qualified production-end people, or not competent enough to realize that they're going to run into a problem without a stage manager or SM-analogue.