When I first got my clear bra, I had the full hood with wrapped edges, bumper, headlights, and the black part just over the front emblem done. My take on it is it's better to have it and not need it than need it and not have it because you can't control what may happen in any given circumstance. I left the other parts unprotected as a compromise because I still wanted to detail it without worries of whether a car product had petroleum distillates or other harmful stuff, which might affect the film.
I've driven interstate along desert highways and even get hit with small debris from big tires and windy days in the city. There are small, pin-like punctures on the hood and bumper where perhaps tiny rocks would have chipped the paint. Eventually, If I know I'd be traveling some rough roads I also use the oem front bra for added protection.
I've been splashed with gushing water from busted city sprinklers spray. Water spots, orange spots (airline fuel), bugs, and bird droppings were safely removed with a quick detailer.
I've been hit on the side of the bumper by another car when parked. Thankfully only the clear bra was scraped, saving the paint underneath. Replacing the current clear film is on my todo.
While some may not have any issues with the paint, it depends on many factors - some of which may be beyond the control of the driver. Like any protection it's there just as an insurance and a matter of preference.