Yes, the US taxonomy includes a great swath of vehicles in the "luxury" main category, even though many of them are not directly comparable. For example, the US market would consider the Audi A3/A4 to be the luxury versions of the VW Rabbit/GTI and Passat, and generally the trim levels available in the US reinforce this: it is very unusual to see in the States any Audi with cloth seats, but not uncommon in Europe.

Hardly any Americans would place a BMW 550i in the "non-luxury" group, least of all BMW USA. It isn't the largest or most feature-jammed car in the fleet, but to Americans it is absolutely a luxury car.