The days when every show gets recorded are long over.
A number of factors enter into the decision, including the existing recordins on teh market and how well they sell.
With GYPSY there are already 4 cast albums readily available (Merman/SONY, Lansbury/RCA, Daly/ELEKTRA, and Peters/EMI), plus the movie soundtrack on Rhino and the TV cast album with Bette Midler on Atlantic. A regional production playing a limited run would never get recorded. (There were hopes that Betty Buckley's revival a few years ago would get recorded. Never was.)
These days when major, long-running Broadway recivals don't get recorded there is little hope for small regional productions to get preserved.
Cast albums are NOT "soundtracks."
Live theatre does not use a "soundtrack." If it did, it wouldn't be live theatre!
I host a weekly one-hour radio program featuring cast album selections as well as songs by cabaret, jazz and theatre artists. The program, FRONT ROW CENTRE is heard Sundays 9 to 10 am and also Saturdays from 8 to 9 am (eastern times) on www.proudfm.com