Since grenadier passive says "Increases Hatred generated from Grenades by 2" I'd expect that it will work for strafe-demolition which says "Throw out bouncy grenades that explode for 187% weapon damage to targets within 9 yards."
Should it not?
But unfortunately is doesn't. I tried to measure the time I was able to fire from strafe, it was somethig about 10 sec and there was absolutely no difference with and with out the passive.