Standard grips help keep the plunger tube on in the event it comes loose, "thin" grips do not. "IF" your plunger tube comes loose and your grips don't hold it in, it can lock up your thumb safety.
Be advised.
Unless one has really exceptionally small hands or short fingers, the thin or thick grips shouldn't make a big difference is one is using a proper grip. I have even tried no grips at all.