If it is actually stiff/dry stuff like glue, that's the only thing that would worry me. Though, if it's soft and could just be excess grease for the screw, then it should be fine and over time will loosen up, I'm sure, could just be a slight anomaly that happened during assembly/manufacturing. As long as it isn't ugly (if you care) or doesn't affect the pair significantly as far as functionality, I wouldn't worry about it. Just going by the pair I have, though, there they are completely dry/clean on the outside and the pivot points move freely. Not loose, but ease of movement.