I noticed this to, and noticed that they lie. Well perhaps not lie but they cherry pick the other homes, and they can be 35 - 40 miles away in a 'similar' area. The only funny part was when I got my PV solar system, which I turned on "to test" prior to them getting through all the paper work. (we were one of, or perhaps the first, people in our general area to get a 'large' PV system (a bit over 5kW)) Our house came in at like 1/10th the numbers of the 'efficient' house but all the wording was written to tell us how we could improve to get closer to the "efficient" house (which in our case would have meant leaving on a few lightbulbs 24/7 :-)

Anyway I realized then that what ever program generated those reports, the programmer had been told that there wouldn't be any 'good' houses so that text never got into the code. I stopped paying any attention to their propaganda at that point.

As that was 9 years ago I'm sure they are much better now than they were but still.