I think it's easy to underestimate just how large and undeveloped the majority of the USA is. England has a population density of 275 people per square kilomet

I think it's easy to underestimate just how large and undeveloped the majority of the USA is. England has a population density of 275 people per square kilometer, 281 if you consider the entire UK. UK also has an agricultural area of about 23 million acres, at 70% of available land. That means that a huge majority of UK land is developed and actively used, and over an area of 23 million acres. The US population density is 36 per square kilometer. That is about 1/8th the population density, which is already a huge difference. In addition, the total USA land used in agriculture is about 900 million acres, which is nearly 40x greater an area. So we are currently at 40x the agricultural land, at 1/8th the population density. The kicker to this is that the US agricultural land use is only 44%. So not only do we have 1/8 population density, 40x the agriculture land mass, we also don't even break 50% of land use for agriculture purposes. This all combines to mean a few things. 1. People that have land in the USA tend to have a lot more land. 2. There tends to be large amounts of unused land all over the place with no development. 3. A lot of land is being developed for the first time, instead of redeveloped. This doesn't directly answer your question as far as needing a trailer vs a truck, but it should give you an idea that the USA is much less developed and a lot more rugged than the countryside of a much older and more established and smaller land mass like the UK. Trucks make it a lot easier to handle all the unexpected situations that occur from having the land situation we have. One other point I'll add at the end of this. The USA also has extremely different and varied climates compared to the mild oceanic climate of the UK. This means more of every type of weather and bigger extremes. This takes huge tolls on both the roads and how tame undeveloped land is. For instance, in the midwest, it is not uncommon for large semi trucks and pickup trucks with huge tires to be the only cars capable of driving on the highway as the highway is covered in a foot of snow and they're the only vehicles capable of driving in it.