You are thinking about this too deeply... it doesn't even show the train tracks cutting through the area. Which is actually where most of the deliveries will be coming from (and shipping out).
I also count 56 parking "dividers" zooming in on the image it looks like each row supports about 10 spots per side or 20 spots (just going to ignore the ends) which would be 1,120 or so parking spots so it does seem a little low for parking, but they are likely to have tons of carpooling and ride share and commuting programs in order to reduce the need for a ton of parking. Think about it, if everyone took a car load (4 people) there would be enough parking for 4,480 people. There is likely to be bus routes and such to and from this building... and given that this is very likely to be LEED Gold Certified they are probably going to require green cars and commuting in order to get a parking spot at all... otherwise you can take the bus (or company shuttle, or whatever they work out).
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I guess my point is, this is an artistic rendering and it will likely look a bit different down the road.