You never can tell why something was there, looked crappy is my guess, or someone damaged it after it was in, or a slab cracked?
My advice, get a home inspection before you close. The building official will do their walk throgh but that is a minimum. I see to many things with new homes that are being missed. For the 3 hundred bucks, you can easily save that in one missed item or incorrect flashing detail down the road.
They have no monetary interest in the home and only work for you, you get piece of mind and someone else to give it another pair of eyes.
Just my 2 cents.