If you are a serious writer, one who (1) loves to write and (2) wants to make a living as a writer, then it makes no sense to give your words away, except as a promotional tool.
If, however, you (1) love to write and (2) would like to share your thoughts with friends, relatives or the world, then by all means, give your words away.
I can't imagine the more successful best-selling authors giving their work away. Their aim isn't to merely win fans; their aim is to earn a living and they can't do that by being altruistic, at least not until they have made enough to pay the rent.
I have an old friend who likes to write poetry. He doesn't care about making a living with his skill; in fact, he has a very high paying job that has nothing to to with writing. The poetry is his escape and his way of communicating his view of the world to his friends and readers. I can't argue with the fact that he sends it by email, and I wouldn't argue if he put it in eBook form and gave it away on Amazon or Barnes and Noble. If it makes him happy, it makes me happy.
As an added note, if I discovered that giving away one of my titles would cause people to buy my other titles, I might consider experimenting with a freebie. I'm just saying ....
