Europeans vs. the U.S.A.

Probably it's just the business models that have grown up in different parts of the world.

From an engineering standpoint, integrated system design is absolutely to be preferred. On the other hand it means that a single designer has to be equally good at speaker design as with digital, mixed signal, and analog. Taking Burmester as an example, their speakers get quite different reviews from their electronics.

It would also be interesting to know how many buyers, European or American, actually buy a complete system from one manufacturer.

I think you forgot about Mark Levinson (as well as Krell) by the way. The Revel line of speakers is an offshoot of Mark Levinson, as both are under the Harmon International banner. (Assuming of course that Harmon allows them to resume production anytime soon!)

I think that in the U.S., the audiophile market is more wide open, and we look everywhere for our products, whether that be in the U.S., Canada, Europe, Asia, etc..
I get the feeling (and I could be wrong), that Europeans buy mainly from Europe, rather than looking abroad. (I get this feeling from looking at their review sites. It seems they review European products much more than U.S. or even Asian products.)

My two cents worth anyway.

I read 'somewhere' (TAS, S-phile), that buying spearates was more unique to the U.S. where in other countries systems sold as a whole...this may have changed over the years. In fact the article stated that some companies (or a company) had to come up with a pricing structure to sell in the U.S. because they sold their products as a whole outside the U.S., but needed to market them as separates in the U.S. Sorry I can't be more specific about the article.