Well, we started from Baycode. We have inherited a lot of systems and atmosphere, as Bay - like CM - is moreso grounded in "Science" part of "Science Fiction." Hell, it took three hundred years from Alien for cloning to appear, and it was faulty then, not unlike Baystation.
Point being: Bay focuses on plausible and critters, rather than "A lizard standing on two legs." I don't think seeing Grav or Space adapted humans around would be too odd, especially when you consider that we know about water-worlds with bases for Space Home-Depot to harvest kelp that was seiged by a cult of literal "Bug-Men". While I wouldn't expect them to be wide-spread (especially for the sacrifice of the ever-important speed and minor durability of humans), a token few would be neat.