The former is an idiosyncrasy that can be accepted -- especially in crotchety old characters who enjoy being feared and avoided. It's almost endearing.
The latter is a pathology which loathes the continuation of mankind on the planet. Hating children is like hating the future, like hating mankind. It's simply not acceptable.
Nice try there Sigfried. I like the attempt at psycho-babble.
I hate snakes and spiders too. They are also part of God's creation.
I just think He was having a bad day when He invented them.
As for kids, when they get past the point of being little sh**z, then I don't hate them anymore.
Its easy.