What is up with these Nicknames?

So you just found that you're going to have a baby? Well, congratulations! And one of the first items that you're going to buy is a baby name book, right? A child's name is very important. Most parents spend months and months agonizing over just the perfect name.
There are so many baby name books to choose from, too! Most baby name books are as thick as 'War and Peace'. They go over every possible name (including Apple and Suri) in every possible spelling, making every effort to give you all of your choices.
My only problem is this. With all of the time and energy spent choosing our child's name, why in the world do we end up calling them by the most bizarre nicknames??
Oh, some nicknames are pretty close to a child's name. For example, I know a Mark whose parents call him Marky or Mar Mar. And then there is little Addison who is often called Add. Okay, so I get those.
I also get calling a child by the initials of their first and middle name, though I'm not sure why the initial “J” always has to be apart of it. I think that we all know a T.J. but have no idea what his real name is. I also bet I am not the only one who does not know what J.R. Ewing's real name was.
And then there are the nicknames that are names of affection. A lot of parents that I know refer to their child as Pumpkin, Sugar, Baby, Sweet Pea, Lovie, Honey, Sunshine or Bear. Sure, those are sweet and a natural occurrence considering the love we feel for our children.
And then there are the nicknames that are spun out of pure laziness. I often hear parents calling their child by just their first initial. I've heard a name of “D” for Dylan, “T” for Tammy or “E” for Eli. Now, are us parents really that busy that we don't have time for the rest of the letters?
Some nicknames also depend on what part of the country that you are from. In the good ol Midwest hasn't every girl been a Sis or a Sissy? I was even Sissy Pal. Boys are often called Butch or Bud here. I've even heard of a Junior who's dad was not a Senior. If you are from southern Indiana like me then you've probably heard of Judge “Tiny” Barthold but still don't know what her real name is.
But some nicknames are very far fetched. I spent a great deal of time calling my first son De De because that is what his baby brother said for brother. I would yell De De to call him at the playground. Other soccer moms must have thought that I was mean for naming my son such a weird name! My daughter's nicknames have gone from Morning to Tiny neither of which have anything to do with her given name.
But my all time, favorite nicknames are those that are body parts or even mucus that comes from body parts. I've heard of a little girl whose parents call her Liver. And, I know this one is hard to believe but I've heard several children with nicknames of Booger or Boog. I personally even know a Booger Boy!
So, new parents, go on and spend a lot of time choosing a name. I've done that too and am now enjoying being a mom to DeDe, “G” and Tiny.