To the ire of some folks, when gray fills up and I'm parked and not moving somewhere else, I hook up an old garden hose and run it off into the weeds, ditch line, somewhere out of the traveled way.
Serously, it doesn't hurt a thing, not stinky, not black water, just 50 gal of relatively fresh soapy water from showers and dishes. We don't wash a lot of food chunks down the drain.
No different than people who take outside or solar showers or toss the pan of dishwater into the weeds while camping.
The "perception" of it is bad because your draining a "tank" and who knows what's in there..lol.
If there are others camping nearby, it's an activity done after the last cocktail as the campfire is dying and everyone else is gone to sleepy land !