I think it goes even a little deeper than that: "help yourself" can be scaled to a level of profitability that is objectively impossible to reach once you put humans in the loop. I don't think that Google is interested in diluting their existing high profitability activities with lower profitability, so whenever they enter a new market like cloud computing they effectively limit themselves to the subset of that market that is open to absence of human support. Just like on the other end of the scale, Oracle is limiting themselves to the subset of their market that will gladly pay extra for the privilege of getting overrun by salespersons.
edit: in other words, I think Google would rather have a highly profitable slice of the market than dominate it and have all the gains eaten up by a greedy sales org.