Sadly, for a large number of haters their hate is their only raison d'être.
Having someone to hate is their way of avoiding self-examination. It's far easier to blame someone else and hate them for it than it is to look inward and see the myriad opportunities one may have for self improvement.
Like right now I'm between two of six time-sucking meetings I have to attend today and I could allow myself to hate everyone involved, I could find another job, or I could go start my pre-lunch Old Fashioned.
For those interested my particular version of the Old Fashioned is as follows:
A dash of bitters
1 part Frangelico
1 part Grand Marnier
4 parts Korbel brandy
(Kind of a given that I'm going for the cocktail, isn't it? )