Fiberglass hood mods... crazy?

I thought a front spoiler would help lower the air pressure under the hood, Since the air is not going under the front of the car as much as it would without a spoiler. Any air going threw the radiator would have less resistance to push right over the firewall and down under the car. Isn't this why NASCAR racing uses front spoilers to help keep the front end low plus lower any underhood pressure so the front of the car does not lift. Just my opinion.