Eighty people had responded to that particular call. No fees, no juries, no returns. This is often seen as part of the description for a mail art call, and is pretty straight-forward. Mail Art is not considered a commodity, and does not have a monetary value. There is no cost to have your work displayed at a show.
All art is accepted to the show as equal and displayed as such.
It would be quite costly to send everyone back their art, so the person that hosts the call often keeps the pieces of art or records them in an archive. Often the person who has hosted the call makes the artwork available for future viewing at their home or another place for fellow Mail Artists. Sometimes a call for Mail Art will say where the art is going afterwards and becomes a traveling show. Mail Art show. Usually after a call for art is made, there are plans to display all the pieces somewhere.