There's also solar, in addition to storage.
All three technologies are really key parts of the future, and controlling that aspect of the suburban home energy profile have absolutely huge synergies.
As we get to higher penetration of renewables, our grid will change from the current model of supplying whatever power is demanded, to a far more two way mode where excess supply will drive time-shifted demand.
Right now the only monetization strategy on the grid for solar/storage providers are 1) net-metered solar, and 2) backup electricity for outages. This will change.
The most expensive component of an EV is the battery, and it's likely we will have as much grid-attached non-EV storage as we have EV storage.
IMHO the current price is unhinged from any analysis, and fully in the tulip bulb stage of share pricing. But I think that Tesla is better positioned to take advantage of three core technologies of our energy future, three techs that must be tightly coupled, and no other player is even really thinking of that.