Belkar doesn't fit with a lot of peoples' expectation of the current OotS, a psychopathic murderous halfling is a bit out of place on a quest to save the world. Back when the expectation for the strip was humor rather than drama, he fit in just fine.

Someone once said, "Tragedy is when I stub my toe. Comedy is when you fall down an open manhole." Belkar is a walking open manhole, and those of us who appreciate the comic first for humor and the storyline afterwards appreciate his presence. For those who expect this stick figure comic to be the epitome of seriousness, it is no surprise that Belkar should be inconvenient to their expectations.

I believe the author gave the proverbial middle finger to the 'over serious' camp with strip #600, and in doing so made an implicit statement that the storyline exists to support the primary goal of comedy, not to replace it.