Maybe convenience isnt really the right word, i can't think of one right now, im pretty tired
Example: Imagine a fantasy setting. Do you like realistic lighting in caverns (where you can't see crap in many places) or do you prefer to be able to see majority of the models and stuff even without a torch? Other examples include situations like being unable to grab hold of things (i.e pull yourself up) when you've already equipped something.
Just a random quip of mine. I find it annoying when i have to light a torch to navigate through most of the dungeon, even though its realistic. I prefer to marvel at the textures rather than being limited to my pool of light.
I do enjoy other moments of realism though, e.g fire spells not working when they hit water, and you actually being injured when standing in a magical beam instead of clipping through it.
Inspiration for these came from Dark Messiah of Might and Magic which im currently playing. Its pretty darn fun and realistic, though the fov is rather horrible. The weapons block too much of my screen, especially when looking at certain angles, pah. Also, kicking enemies off ledges is really enjoyable as well as kicking them into traps. And spikes. And fires.