I would argue that, at least so far as the original novels, the Gully Dwarves existed to make a point-- specifically, everybody looks down on them. They get treated like burdens and living trash... except by Raistlin. The resident asshole of the group, who at first glance seems to be on an edgy quest for power-- the unexpected tolerance and empathy Raistlin shows them really humanizes his character. He sees how other people treat them, it resonates with what he went through before learning magic, and those interactions reveal that beneath his demeanor Raistlin is strikingly human and even a little vulnerable at his core.
You're definitely meant to feel like "the way they get treated really isn't fair". Because that's the whole point-- Raistlin, of all characters, feels that exact same way in a world that doesn't really tolerate these smelly, dim-witted creatures. And through that, you start to empathize with and start to understand Raistlin beyond his quest for power, and why he pursues it so single-mindedly.