Why is RB Leipzig hated? 

RasenBallsport Leipzig e.V., commonly known as RB Leipzig, is a German professional football club based in Leipzig, Saxony. 

The Bundesliga is a professional association football league in Germany and the football league with the highest average stadium attendance worldwide. At the top of the German football league system, the Bundesliga is Germany's primary football competition.

Steffen Prößdorf, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons