If you read the letter, it clearly states that the estimates are based on house size. Of course they don't know how many people there are or any of the other circumstances, but that's for you to consider yourself. The information can help you make informed decisions about how you use electricity. If your usage is way above that of others you might have a problem that can be fixed and save you a lot of money.
Since your energy bill fluctuates due to weather, how do you know if the fluctuation is normal or if there is a problem? My January bill was 20% higher than my December bill. That makes me wonder if I have a problem or if it's just the colder weather? So then I get the letter from SMECO, and it shows that although my usage went up, it did not go up as much as others and I was still 5% lower than my most efficient neighbors.
When my heat pump failed during the winter I was not aware of it until I saw a big increase in my usage. That kind of problem can go unnoticed if you have no frame of reference.
When it says "neighbors" they aren't referring only to those on your street. They are talking about 100 other homes in the area of comparable size. But since weather is regional the comparison is still valid.
You are free to completely ignore the letter. Just throw it away with the rest of the junk mail. Why get all worked up about it?