I agree that owning real estate doesn't seem a big issue to me, but urban design does: I lived on both sides of the pond and in the USA getting to a party usually involved driving somewhere. That means organizing to go there with a group and a designated driver to stay sober, or getting a taxi (too expensive, when I was young). In Europe, I could just get on my bike and show up by myself. That lowers the barrier to entry considerably. As far as I can tell, urban sprawl in the US has made it even more car dependent today than when I was growing up.