I'd guess it has to do with which charger company VW Europe and VW North America are partnering with to sell the vehicle. Vehicle-To-Grid is coming along in the US, and could still be possible for some/many buyers, but it depends on your charger and your utility. V2G was a big sell from Thomas/Freightliner guys when I bought the EV bus (240kW of battery) last fall, but our [very progressive] utility is still a few years out from being able to actualize it on their market.
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