I'd expect the wealth-corrected data to make the EV owners look even better, since they'd be comparing them against households that use even more electricity than their baseline typical customer.
To be fair to the author, I think that they actually can't do the more detailed comparisons because they just don't know enough about the households in the study. At the end of the page, it explains that they don't even know whether or not the households actually have EVs, they are just guessing based upon their electricity plan. So despite the earlier talk of stats like "53% more likely to have a swimming pool", I suspect that this is gleaned from elsewhere and their dataset contains very little about the customers, and probably not enough to be able to break them down by income or other factors.
Interesting, I'd expect the opposite - It's easier to be more cost / eco efficient when you have the money to. You can, for example afford a modern and robust car (with a great catalytic converter) and regular maintenance. You can afford proper insulation and home automation systems that shut down unused resources, etc. You can afford to pay for composting and recycling services.
It's easier to be more cost / eco efficient when you have the money to
Of course, but being more efficient isn't the same as having a smaller overall footprint. The point is that wealthy customers probably have bigger houses that require more energy to heat and cool in absolute terms, even if it's done more efficiently relative to poorer folks.
Be careful with that assumption. My previous 2000 sq ft house cost less to heat and cool than the earlier 900 sq. ft. house we moved from. One having been built 30 years more recently than the other meant that the insulation was of far better quality even though the older house was much smaller and had an almost brand new HVAC system.
To be fair to the author, I think that they actually can't do the more detailed comparisons because they just don't know enough about the households in the study. At the end of the page, it explains that they don't even know whether or not the households actually have EVs, they are just guessing based upon their electricity plan. So despite the earlier talk of stats like "53% more likely to have a swimming pool", I suspect that this is gleaned from elsewhere and their dataset contains very little about the customers, and probably not enough to be able to break them down by income or other factors.