It is certainly a cultural divide: In Europe, the UK, and across the Arab world, an arranger keyboard is the professional performance instrument, used with pride and to great effect. Here in the U.S. the category is mostly looked down upon, and the sight of onboard speakers or a button labeled Ballroom often sets off jokes and sneers.
Having been on both sides of the fence....playing music in Europe for many years and now here in the States, my observation is this. Americans, who have never been out of this country, really don't understand good, diverse music. They listen to a LOT of jazz, the Great American Songbook (which actually IS great), your standard genres (disco, rock, folk, C&W, etc). All well and good, but it never gets expanded on. In Europe, on a gig, you'll hear the Blue Danube Waltz, semi-Classical, things like that circus-song Zirkus Renz.
What I'm leading up to is: that's the reason an arranger is more professional and more respected in Europe. They make full use of the board and all the styles. Here I don't think most arranger players use more than 1/2 dozen styles. And very rarely do you hear someone really give the "instruments" a workout.
I remember when I recorded "Until It's Time For You To Go." Intro was vibes with strings on left hand, then the "whistle," then lead strings on the release, then violin, French Horn, and back to vibes to end the song.
And then there are marches! Exciting, electric marches! Who plays "marches" over here on their arranger keyboards?
All that wonderful European music really inspires you to play and open yourself up to creativity. That's why arrangers are frowned upon here. The music being played doesn't lend itself to full utilization of the keyboard.
Mark