As a UK resident, I see a number of differences between Euro trailers and the kind of trailers often modelled in the US. Do they use 'Super Singles' in the US? Super Single wheels and tyres are universally used over here, they have wide tread tyres used singly instead of doubled up (2 to an axle instead of 4).
In North America, super singles are not too common but are mostly seen on gasoline (petro to you) tanker trailers. You can on occasion see them on fleet tractors
(if there is any space), to prevent cars going underneath in the event of a crash. Similar bars are on the rear end.
Under run protection is only required on the rear of trailers. Possibly due to North American passenger vehicles on average being larger than Euro passenger vehicles, or possibly that the trucking industry lobby is so strong that they prevent that regulation.
I think different materials are used to make 'em too - not so much ribbed sheet metal or polished aluminium on Euro trailer bodywork.
The tastes of Europeans, like the European autos are less flashy than North American’s.
Also, the trailers just look different in terms of size and shape. Well, they do to me at least. This is probably a result of the generally older European highway network having tighter bends and lower bridges and all that. Small diameter wheel/tyre sets are often used to allow higher bodywork to be used and still fit within load height restrictions.
Older narrow roads and shorter distances.
These are all reasons why I enjoy modelling US vehicles, it's a different look to what I see everyday on the road