They're not trained for that. Oh heavens, don't they know they're not trained for that? They'll lose their razor's edge!
Tell them there aren't any roads.
Tell them it's all quicksand.
Tell them they'll be destroying 'Horny Toad' habitat by the gazillions of acres.
Oh, where's PITA? Has PITA heard? Those poor, poor 'Horny Toads'.
Quick, where are the force multipliers? ;^)