Rather than self-indulgence the Koran promoted self-denial, so as to eliminate or reduce the evil ways aforetime popular.
Self-indulgence and self-denial are however -- in some way -- two sides of the same coin, minted of the self.
The Arabs seem to have an acute weakness in that area -- just speaking to the history then, and the modern history.
I think that weakness for extremes of self-indulgence and indulgent self-denial became to be exploited by a historical stream of people bearing a love for death -- assasination, martyrdom, etc. And that those life-rejecting ideas caught a foothold in Mohammed's teachings.