Did the dealers also tell you why they prefer to sell Yamaha instruments above all other brands? I think i know why, you can make more money from selling a Yamaha instrument then you can make from selling any other brand... combined with the great backup support they get from Yamaha over here in europe, that makes them want to sell Yamaha first and above all..
Over here in the UK Yamaha organs/arrangers are part of a family (Has been from the late 70s early 80s) so people feel happy with the Yamaha brand (Just like Apples users do with their stuff) and they constantly recommend it, even though it falls short in a number of departments. (Just like Apple products)
If you can get a licence to sell Yamaha (You have to meet strict support guidelines etc.) then it is quite simply a sure fire way to print money.
Bill