@7f60fbe4 you aren't a big traveler, are you?

Get on a train in Amsterdam with your luggage, arrive in Brussels with your luggage, haste through the railway-station onto a commuter train to Zaventem and get out there, schlepp your luggage into BRU and finally start your check-in

OR you can check-in at  Schipol (AMS) and lean back.

That's also the only reason why you can fly from Hannover to Frankfurt. Nobody wants to do that - except if there's a connecting flight from FRA