The issue was occasionally raised informally by individuals during my five years in the chair. My view was that it would tend to create a master-servant type of relationship. I wanted to keep it voluntary; I was actually on the EC to help protect my investment! If asked about payment, I might have nominated a black cartridge for my printer as a goodwill gesture. Ultimately the incoming EC spontaneously gave me a gift card after I stepped down, and I appreciate that.
One or two individuals acted as if the master-servant relationship existed, and one still does, but I suppose you get them in every building.