Yeah, no kidding. I've always realized that of this genre though. The verbosity of the medium allows for them to develop and explore themes that other games would merely gloss over, it can definitely make for some emotionally affecting stuff.
Hah, the first thing I thought of when considering a game that's even managed to touch something of that intense emotional calibur was Planescape Torment, which - now that I come to think about it - was half visual novel already in the sheer amount of writing it had.