After so much Int'l Travel for High Tech Biz, I think it's a 'Chicken And The Egg' sort of question.
Smaller Land Mass and Countries there lead to more compact Town layout, and smaller Dwellings. A good German Pal just laughed at a 3/4 Ton Truck in a monstrous Parking Lot at a Big Box Store here where I took them to replace a piece of Airline-shredded Luggage. 'Who needs such a Truck', they asked me in astonishment! From the former East Germany, they also could not believe the number of choices here of, say, Cereals in our Supermarkets. Even that Inventory requires 'more' space.
This thinking - good, bad or indifferent - has lots of implications. Caravan Parks are smaller; areas to store your Caravan are smaller; and so on. Some months ago on this Forum, someone pondered why the German vs. American VW Passat [I think?] Towing Specs were so down-rated here in the States. The consensus was that it was either a Warranty avoidance issue, or a CYA issue from the U.S. arm of the Manufacturer. It wasn't a technical issue [Engine Torque differences, etc.]. The Vehicle capabilities were the same.
I drove by a Colorado River-side RV Park yesterday by I-70. The Big Rigs were out; Slide Outs deployed; Satellite Dishes up and oriented. No looking down my Nose intended at all. Culturally, in more compact Land Masses, Campers get out to experience their 'limited' bits of Ma Nature in Europe. Hike, Fish, Picnic, take Pictures... Further, putting a RV on a Ferry [which I've done] to vacation in, say, Norway is priced by Vehicle Length. So, The ~22' Class B we rented came in JUST under one length 'Category' on the Ferry [~7 Meters long]; a reasonable Ferry price to pay. And, it was fairly easy to drive through tight Villages in remote Scotland. Fortunately, the side Mirrors 'snapped' in and popped back out when you hit something. Just once.

Also, the necessary wide turn coming out of, say, a Petrol Station on a tight Street while towing a long Rig is a maneuver that might take you 'forever' while you wait out Traffic.