Judgment over finding out gender

Since I've decided to find out I've noticed how much judgement there is about it. I can't wait to find out, I have a slight preference for a girl but I really don't mind, my nursery is already decided & it's gender neutral. there's a million surprises when having a baby why shouldn't we find out one them before they're born when there's so much Unknown? 
 Will they be big/small? My eyes? His nose? Chubby? Thin? Will they have hair? What will their personality be like?
I personally don't understand why people wouldn't find out but I don't judge or make fun of them but there's so many people who do of those of us that choose to know