"What could be more exciting than that?" Canderous asks, rhetorically. "It's got to be more interesting than here, at least. What you're doing on this dirtball when you could be out there, I couldn't guess."

What you're doing on this dirtball, rather than out there in the stars with the rest of Malak's fleet, is what he means. But Canderous keeps his voice high-spirited, and it's somewhat borne out of genuine curiosity. Besides, this planet is dull, unless you were a Jedi and liked meditating in the fields or something as equally useless and boringly pointless as that.