Damn Mud Flaps

well.my front mud flaps seem like they're super long. because when I go over some bumps in the road they scrape along the ground. are there any real advantages to keeping them on other than keeping the car a lil cleaner? and in the fall when I'm cleaning it out before winter there's always like leaves stuck between the inside of the fender and the mud flaps..should I jsut take them off?

I also heard that they induce rust too..is that true?