You must play in a very different style of campaign than I do. We treat darkvision in total darkness as being pretty awful light quality, which, IMO, is exactly how the game describes lightly obscured. It's bad enough that you have blanket disadvantage to see things, and you have no color perception. Reading is much more difficult if it's possible at all, and most tasks requiring skill or knowledge on top of the ability to see what you're doing likely are difficult or impossible, too. It's worse than being a human in a room with a single lit candle, because a candle casts a small amount of bright light and you can still perceive color. A single burning torch throws 20' of bright light, how dark must dim light actually be? If you personally would be uncomfortable doing something 10' from a candle as your only light and you can see color, then these fantasy creatures feel the same way about total darkness. Most things carry light unless there's an imminent ambush.
That's why even Drow have luminescent moss in their cities. The only creatures that routinely rely on darkvision alone are those incapable of creating light. Most of those creatures have hearing and scent to make up for the deficit, or otherwise are only concerned about hitting you.
