I was at a wedding many years ago in California, and was close enough to watch what the organist was playing, He had a full set of bass pedals and was playing bass with his feet using an alternating heel and toe method, some of the things he played had a non-church progressive rock type style to it.
He was awesome.
Yes Ray Manzarek played that little Fender Rhodes bass live, but sometimes the Doors had a bass player in the studio. Lonnie Mack played bass on Peace Frog and Jerry Scheff played bass on the LA Woman LP ( His son Jason plays bass for Chicago) there might have been others, but I'm not sure.
I think Devo used the Rhodes bass on Whip It as well.
and don't forget John Paul Jones playing bass pedals and left hand bass in LZ, Geddy Lee from Rush, Mike Rutherford from Genesis and a band called Zebra, bassist/kybst Felix Hanneman does killer left hand bass !
B.