From my best count there are 27 model/units in the entirety of Hordes (not warmachine for any of this, mind you, just Hordes) that have sprays. Two of those sprays are from the spell Crevasse which needs to kill a model with a direct attack to create the spray. And two of those models are named Grissel while two others are named Thagrosh.
Of those 27, Trolls have...
3 Fell Caller Champions
4 Scattergunners + UA (I'm only calling this one unit, mind you)
5 Winter Troll
7 War Wagons
8 Mountain King
9 Sons of Bragg
That's 1/3 of the sprays in Hordes. And it doesn't take into account that the Road Hog and Scarath can be used under the control of lesser warlocks in a troll army as well.
Oh... and one of the sprays we're counting is the Doppler bark. 2 of them are the spell Crevasse.
Yeah... that's how much we're scraping the barrel's bottom.
Now... I notice another thing about the list above. A significant portion of it are models people on these boards don't seem to respect.
And this makes me ask, "how do we, as a faction, get more mileage out of our sprays?" as I think it relates directly to figuring out the next step in Trollkin evolution, competitively speaking.