The sugar won't burn until it reaches 375*, hopefully we're not Q'ing at that temp.
When I make a rub I leave the Kosher Salt and the Turbinado in it's original form. If you arre familiar with any of the Dizzy Pig Rubs they are quite coarse compared to some others I have seen.
It won't hurt your rub, IMHO.
Treasurer, Great Lakes BBQAssociation
Rubbed, Smoked, and Sauced Competition BBQ Team-
22 1/2" WSM, 2 18 1/2" WSM's, 22 1/2" Weber Kettle