Just depends on what part of the year it is. If you're down on the deck of the boat, where I sit quite a bit to take cool photos, then yes, you're getting hit with grass and bugs.....but only while going through the tall grass
If you're sitting up on the seats, which are high off the water/grass, then everything just lands on the deck and blows off while driving. If out on the water, then you only have the option of getting hit by fish jumping into the boat when you shine them at night
This particular night, we were running along the shallows and hit the water with a big hand held spotlight, and dozens of fish jumped in the boat. The girls were screaming and one got put down my wifes shirt in the antics. Good fun had by all