1. The US is much larger than the UK, with a lot of nothing/low population density.
2. Mentality might be different: I imported my current car used from the Netherlands; the country is tiny, but the Dutch seem really like driving a lot. I saw many cars with 30k miles per year on them.
I'd say most of the drives are commutes to work and shopping.
There's also zero useful public transportation for us. If I worked in the city, I could take the train, but it's 4 miles to the train station.
Now Germany has a population density of 621 people/mi². The US has a little less than 100. Assuming similar interconnectness (family, friends, jobs, holidays), travel distances are much larger.
There are lots of other reasons to think it is unreasonable, but from the perspective of someone who sees their trip to work as half an hour it doesn't seem bad.
