jay: water "spots" are often much more complex than simple dust and scratches. For example, at the end of my film, there is often a "spot" that runs lengthwise down the last few frames of the film. These sorts of "spots" are much harder to automatically correct, as they're not true "spots" but rather are large blotches and irregularities that interfere with the details in the image itself. Indeed, there have been a couple of times when I've thought "what an ugly image" until I realize that some of the ugly "detail" is really a large, oddly-shaped patch of water/Photoflo residue*.
Maybe you're luckier and/or have a better method of drying your negatives. I dunno. But I do know that I've been using Photoshop for over ten years and am well acquainted with the healing brush, dust and scratches filter etc. I can say with confidence that these tools aren't much help with the sorts of "spots" problems I have; I'd imagine if someone is in here complaining, they probably have the more severe "spotting" problem like how I have.
*I'm blaming Photoflo because I still get these problems even when I use Photoflo with distilled water!