why do people write blogs????

this is my first blog and i am trying to find why the hell people write blogs or rather why i am writing a blog? the reason behind this can be many ranging from giving a structure to the thought process to some abstract reason like i have no work to do so i am writing blog.
lets explore it more through understanding the basic philosophy of human. a man can't sit idle and therefore he needs some work. is it that people like me who have no work, start writing blogs. No, bcoz even if person has no work he can do something else like walking, talking to friends etc.
is it possible that a person writes blog to pass his thoughts to other? i dont think so bcoz neither a person is aware of the profile of readers nor he knows will anybody reads his blog or not. can then reason be that he just wants to pen down his thoughts so that there is space for other thoughts? this again is conspicuos as atleast in my case i hav no thought but just to write a blog, i am writing.
but a person like me who doesn't even want to type the assignments and reports is typing a blog, so definetly this cant be "just to write" bcoz of which i am writing. is there something else governing me or i am writing bcoz these dayz blogs are "in".
but a person like me who doesn't care whether people think me hap or not doesn't get affected by what ppl say abt me ...cant write just bcoz of fashion.
after analyzing all these reasons now more and more i believe that i am writing to kill my time as i have no other work to do...but why blog???
let the reason for time being be assumed that blogging is done to kill the time. so now lets think what people or rather we ourself used to do when there was no blog to kill time...rather i can think of yesterday only as this my frist blog i used to do all those old faishoned things to kill time till yesterday.
i used to write poem, to sleep, to walk, to sing in carnivorous voice...and what not??? i would have used this time to do something creative or rather to relax but not in doing this wasteful activity.
though i know that i am wasting my time then also i am blogging so is it that i still dont know why i am writing??
now i can tell u there is a mystery behind evrything when u blog that is u dont no who is going to read and what the comments are going to be like but in anticipation of some feedback that to from a person u dont know u blog. that is a person needs true feedback but when it is given in a direct manner ppl thnk that either the person is diplomatic enough that he is praising the thoughts or he is not learned enough that he cn understand my blog( in case of praise and criticism respectively). Which reduces the chances of taking feedback in constructive manner?
but still i think i am not writing this blog to take someones feedback as neither blogging is my passion nor i want to see like minded people.
then why am i Bloging????