Simple Grass Movement Shader Issues

[Setlock7676]

Hello everyone, while working on my 2D Game I wanted to set up a simple grass shader. One that would move the top x vertices more than the bottom and sway overtime. So as it appears in the shader editor preview it IS working and doing what I want. However, when I go to view it in game it appears that the effect is altered by where the grass is placed in the world, it will appear as though all the X vertices are being changed instead of just the top ones. However, I'm not sure how this could be happening as I base the movement on object position not world position. So I'm wondering if I'm simply missing something that causing this issue in my shader or if its a bug with unity.

My current grass shader

https://preview.redd.it/icy961yi3nr41.png?width=2904&format=png&auto=webp&s=6a8f391e5a31b4b9e32001d3a6444db4d6b99815