Agreed. There are many flavors of moats. I originally wrote something more complex but it quickly turned into an amateur HBS study about Google. I hope the point is interpreted more metaphorically.
I may be wrong, I'm (mostly) a DL hardware guy, this is just my two cents :)
Even for the long tail? I'm pretty skeptical of this.
If you do your research on google and then buy from amazon or somewhere else and don't use the adword link google's business strategy fails.