In this he hearkens back a century, to the days of Morgan and Rockefeller. Many financiers agree with Arnold's assumption but, since Arnold is the faster talker and has the bigger bankroll, he might seem like a good horse to bet on. If, that is, the assumption is correct. It's true there are barriers to entry in the e-tailing space. Scaled fulfillment is one such barrier.
Brand can become one, if the brand has credibility.
Unfortunately none of the brands Arnold and his ilk are looking at have credibility. The key Clue to today's market is simple - bet on the jockey, not on the horse. Jeff Arnold hasn't proven he can ride an ass. Figure that out and everything else becomes easy. Google figured out its one thing was search.