Nah.. looms are used to combine strings or fibers, not extract fiber. But on a side note, you could use a loom to weave grass. I mean... the grass in the game is certainly tall enough!!!
When we get into primitive crafting, everything primitive needs to be limited to the personal crafting section, not a workbench.
Something like this would be neat to weave out of long grass. When it dries out it would look nice. http://www.dreamstime.com/stoc…at-isolated-image19357113
For making haybales, there's lots of modern tools that you drag behind a tractor. As the grass is cut, its fed into the baler and the thing just automatically pops out a compressed hay bale whenever it gets full but I think for making a primitive one, its just a matter of using a pitchfork (we need one of those too) to make a pile
Maybe some additional recipies in the personal crafting menu will become dependant on which tool you are holding in your hand or have in your inventory