Jim,the material can be shared once the songwriter gives permission,and in the case of say a publication[Like new city songster] comes to some agreement, about waiving royalties.
I see Folk London regularly publish new compositions,they clearly do so with the songwriters permission,and have come to some kind of an agreement,so it does clearly still happen ,that people come to arrangements[perhaps waiving their royalties,or any income due].
but this is done with the songwriters permission.,probably in the case of Folk London,the songwriter has approached them.
So can we stop this harking back to the good old days of Ewan Maccoll,it is extremely tedious and backward looking[reactionary]