Upvoting once own comment should only be done when you want the authors attention or convey a important message for the author. Other than that i think self upvoting once own comment is not a good thing, unless of-coarse you are also upvoting others.
The problem with new steemians is that they have a wrong perception of steemit. They think that it is get paid to post anything. Thus they comment randomly on any post with out even reading it. They think that they will earn as much as they comment on other's post. Well this doesn't last longer though since they will soon start running into bandwidth issues.
In order for spams to stop people have to stop rewarding them. There are some people who i have seen, upvote every comment on their post even if it is spam. They should actually stop doing this.