They lower stress

Sometimes I think it might be nice to have office pets hanging around, like a ship's cat or something. Of course then we'd get arguments about whose responsibility it is and whether we can swap the cat for a dog or vice versa. The people with allergies would demand its removal and the others who never see it might ask to be moved closer to its usual territory.

The general point is that we go to some significant lengths to create a sterile, dehumanised working environment, then wonder why our workforce is stressed.

Mokalus of Borg

PS - I advocate a friendlier work environment whenever possible.
PPS - That means personal touches.