Photographer here, from back in the early 2000's (still shooting FUJIFILM but just for fun), and yes, I did use lens hoods, for the most part the glass on a camera is a bit more exposed than that on a scope however. I've got no issues with anything mentioned in this post, it just has my wheels turning, that's all. My experience of testing scopes for this came after a ghosting issue at a match that likely kept me out of 1st place on the shooting portion, so I went about a week with multiple optics against the sunlight at various hours and angles. Doesn't mean there is isn't something here I missed or can learn.
As for
@koshkin saying the light is not reduced with a sunshade, well, I trust him much more than myself, but I have two things that make me skeptical about that:
1.) Removing the sunshade at dusk seems to help extend shooting light a bit in the woods
and more importantly
2.) Going back to cameras, I can set a camera in aperature priority mode, set it up on a tripod without a sunshade and note my shutter speed. I can then put a sunshade on and the camera automatically decreases the shutter speed. This right here seems to be pretty tough to dispute.