Most people dont have to drive from new york to los angeles or similar, thats 42 hours, but we have similar distances in europe as well. The longest ive driven was about 30 hours(dont even ask, thats too much even for me) but a friend of mine and their family had to drive down from åre to barcelona which google maps says is 37 hours. I think it took four days for them. Also from where i am right now, kiruna, a very northern city in sweden, is 18 hours away. The lomgest drive in sweden wothout going through another country is 22 hours so the us being larger isnt a very valid argument. If you look at the entirity of europe its larger than the us and the distances are longer but what actually matters is the population density. When comparing the contiguous us and the eu for example the population density is double in the eu while the whole of europe has a population density about 50% higher than the us.