Its because they where created to make music like this with duos trios or even OMB.

Video

This video is shot in my hometown, and while not the highest level of quallity, it shows why many people overhere in europe like this kind of partymusic... It makes people happy and they all sing along... Music is about emotions and this shows much of our european emotions...

And this kind of music is what Yamaha and Korg have in mind when building Arrangers...