Several reasons for this appearance of better than great fuel economy….assuming the math and conversions are correct.
1. Short trips, partial fill ups especially on the top 1/2 or 1/4 tank are notoriously inaccurate.
IE a couple litre difference on 30l fill up will change the numbers 4x as greater than a couple liters difference between fill ups on a whole tank.
2. You don’t know the wind conditions, you may know the road, but wind plays a huge part. And sometimes it blows the other direction from prevailing winds even when you’re living on the bottom of the earth and not the top…
3. Most men lie about 3 things. Size of fish they caught, size of their 3rd member and the fuel mileage of their truck.
4. Based on your decided bias for the down under and your years of repeated America bashing on here, I don’t believe you any more than the owner who supposedly posted their mileage.