Comments sections are a necessary evil in the world of webcomics. I know creators dread the anonymous comments, but most feedback does help the creator improve their writing and/or artistic abilities. Also, I have been told by more than one expert in the webcomics community that people tend to read webcomics that allow comments.
A bad comment is hard to shrug off at times. I introduced Phoebe and Eddie, a webcomic, to a webcomics forum and it was pretty much ripped to shreds in the comments section. Like an idiot I went into the comments section swinging away and it only made me look foolish and too immature to survive this business. That was truly a learning experience.
I've learned to not comment when someone leaves a negative comment. I know this sounds like something you hear in a cheesy public service announcement, but you can learn from mistakes without attacking your readers.