Predominantly self voting one self is absolutely unhealthy for the community at large, if everyone did that, the community would get really stagnated and only a couple of people that can significantly upvote themselves would be rewarded.
This will be very discouraging to newbies may actually reduce the number of sign ups.

Very, very well said. I think that if we look at it that way, we will all try to spread the votes around, regardless of whether we give ourselves some of our own votes too.