That's a great question. As a kid, I took great pleasure in annoying teachers, relatives and people in general with that very question. My parents always told me I was gifted or some such nonsense "because I dared to ask the infernal question 'Why?'".
You would think that, if you ask a question enough times of enough people, you'd get a decent answer. So far, I haven't found a really good answer to it. The problem, I think, is that there are so many iterations of the infernal question.
Why is the sky blue? Why will the Rangers never win the World Series? Why is flatulence funny to guys? Why blog? Why call it "Preachers and Horse Thieves"? Why the heck should you care? Why ask why?
Obviously, some infernal questions are easier to answer than others. So here, in all its glory, is the eternal answer to the infernal question (with further exposition as necessary): BECAUSE.
Why Blog? Because I enjoy reading and writing. Because my wife, the ravishing, red headed queen of my castle, said I should do something as a creative outlet. Because you can do it for free. Because it's therapeutic (no, I am not in therapy nor do I want to be).
Why call it "Preachers and Horse Thieves"? Because it's my blog, and I'll call it what I want. Because my mother, the family historian/genealogist has file cabinets (yes, cabinets plural) full of everything imaginable documenting our family history and loves to tell stories about ancestors who were preachers or horse thieves (and one talented individual who managed to be both).
Why should you care? Because almost all of us have preachers and horse thieves in our families. Because when you think about it, most people around you are either preachers or horse thieves. Because there's always someone preaching about "global warming" or how your 9 year old, paid for car is killing the polar bears or how your lifestyle is evil or something or other. Because we have a government full of horse thieves who want to steal your stuff.
Profound? Probably not. Interesting? Maybe. Thought provoking? I hope so.