I've noticed and I'm sure some of you do too that there is definitely a cultural difference in comparing the bluegrass audience and the folk music audience (here in Canada anyway ). For example not too long ago before they outlawed smoking in the bars here if you went to hear bluegrass in any club around Toronto you could count on it being a smoking pit and a noisy audience (even though the performers may be top notch).(Beer available stuff and most popular -light beer and average like stuff like Molson Canadian). Go hear folk music at a club or pub - audience is quiet, attentive, (many premium beers on tap as well as light). The folk music audience is open to a wide variety of styles, and bluegrass audience is just focused on that style and it's culture for the most part.
I recently recorded a banjo CD "The Banjo Special" with bluegrass, old time, and Irish music all on the same disk. High hopes were made on bridging wider audiences with the recording with some success - but it did not meet expectations. The reviews on the recording of the individual genres were excellent, but acceptance of listening to the non preferred style of the listener remained difficult.
Observations. I love good music.
Arnie Naiman