Sounds like a good question for Koji Fox.

My personal theory is that while the effect is similar, the method is differing between what we do and what people outside the twelveswood do, similar to how many wrestling techniques in our world have many similarities, even if they have evolved in different places and using different training methods. That's just how things work. For those who follow the Gridanian school of Conjury, I suspect its mainly a case of the individual showing respect to nature. Elementals don't really care about politics, morality of mortals or mortal laws.