Most enthusing about sessions in pubs are players, not singers. Whatever is played in a pub session is treated the same as background music as during the playing of it, conversations continue, drinks are ordered and there is no audience, those playing are playing entirely for their own amusement.

A Folk Club is different. It is normally held in a designated space that has been reserved for that specific purpose for that particular evening. All those present are there to listen and participate. The material performed to widely varying degrees of competence ranges from traditional to pop, and, no sorry the latter is NOT folk music, even if it is being sung, normally appallingly badly, by "folk".