You just gave my thoughts a voice. However, thinking back to the days I began on steemit, I was also shamelessly self promoting my posts in few comments. No one responded to it, possibly because my comments were bordering enthusiasm and not spam.

I think with recent boom in user count, this will happen for a while. To overcome this, we should simply down-vote repeat offenders (we have to spot them across blogs). This will give them a sound message, if they don't heed to initial warnings like your post.