We have a similar issue here in the UK with PRS. Part of the difficulty is that these "music industry" models don't really suit the small-scale and informal nature of many folk music performances.

Last night I played at an informal, unplanned session. I can't remember what we played. I don't know the names, far less the copyright status, of half the tunes I led myself, never mind the others. It would be impossible to submit a return, whether in the old paper format or online, and I very much doubt that events like this are ever sampled. The venue still has to pay for a license, but I would be very surprised if any of the copyright holders ever receive a penny from these types of events. However it is events like these which make up a substantial part of the performance of folk music throughout the country.