•“commensalism” regarding sharing food and dining together implies that something is owed to another. what is owed in commensalism?

I think the one that is owed is the fact that one organism can sustain its living without that other organism.
For example, remora fish that got its food from the residual in shark's mouth. Technically the shark will not affected by the Remora's activities, but he remora owed the shark big time.

Used to water and cool climates, probably not thick coated or fluffy. they most likely have thin coats and have to survive to find food. sorry if this wasn't the answer you were looking for..: )