My overwhelming impression having been in many many mixed folk sessions is the inherent niceness of the participants. Singers who can't sing in tune,players who can't play in tune and percussionists who can't hit something in time;all are welcomed and none belittled for lack of skill. The key here is people are having fun.
By and large people gravitate towards settings which suit their personal preferences. If you don't like a particular setting or format go somewhere else. John