Not much of a betrayal to be honest. I don't know if anyone has ever mentioned this but Mario Goetze was a Bayern supporter when he was a kid. You can dig up some articles where his grandfather said Mario slept in Bayern comforters as a kid. His father and grandfather are also both Bayern supporters. So in a way, he is coming home. It should also be noted that Goetze has several transfer requests with huge offers from other clubs. He just does not want to move out of Germany. If it's really just money he wants, I'm sure he won't stay at Dortmund the minute a big club tried to sign him.
Besides, even if Bayern and BvB are current rivals, the rivalry is not as big as Real and Barca. It just look bad now because BvB swept the title against Bayern two seasons in a row. The ultimate betrayal would have been Goetze transferring to Schalke (bvb and schalke are arch-enemies) or any of the Bender twins (1860 Munich homegrowns) transferring to Bayern (1860 Munich and Bayern are arch-enemies too).
And buying the best talent in the league is not just Bayern's forte. It is Dortmund's too. I understand BVB plays very entertaining football but we should not be blind to their management's faults. BvB bought Marco Reus from Gladbach in the exact manner as the Goetze transfer but no one bats an eye. Klopp sent Mourinho-esque type of digs to Bayern but everyone thinks it's amusing. Don't get me wrong. Klopp is one hell of a tactician but off the pitch, he talks like Hoeness a bit. I don't understand how easily he can get away with some things he say.
Thanks for pointing out the rivalries correct, because Dortmund-Bayern rivalry is indeed pretty recent (although they were rivals in the mid-late 90s too).
Other than that, the last paragraph contains a lot of wrongness.
1. Bayern have a rampant history of systematically weakening league opponents: Some examples to put things into perspective:
- Calle de Haye and Lothar Matthäus from Borussia Mönchengladbach in the eighties, weakening the only real rival in the league.
- Mid-eighties: Nürnberg becomes a serious contender: Bayern sign Hans Dorfner, Stefan Reuter, Roland Grahammer and Manfred Schwabl, effectively banishing Nürnberg to mid table again.
- 1989: Köln become a serious competitor: Bayern buy their by far best and most important player Jürgen Kohler.
- 90s: KSC becomes a serious contender: Bayern sign over the course of a few years Michael Sternkopf, Oliver Kreuzer, Mehmet Scholl, Oliver Kahn, Thorsten Fink and Michael Tarnat. In 1998, KSC goes to second division
- 1991: Kaiserslautern wins the league: Bayern buy Bruno Labbadia. Two years later, they buy Marcel Witeczeck and Ciriaco Sforza. 1994, Kaiserslautern go to second division
- 1995: Bremen become a serious competitor: Bayern buy Andreas Herzog and sign Rehhagel, one year later they buy Basler too. And the Bremen-case repeats here: 2005 they buy Ismael, two years later Klose, 2008 they buy Borowski. They even signed Jan Schlaudraff just so that Bremen can't get him.
- Stuttgart case: Bayern destroy the 'magic triangle' by signing Giovane Elber.
- Around the turn of the millenium, Leverkusen becomes a strong opponent: 2001 Bayern sign Kovac, 2002 it's Ballack and Ze Roberto, Lucio in 2004.
I'll stop here and believe me, this list goes on and on and on. Trying to relativize that with the Reus-transfer is inappropriate. And fyi, Dortmund signed players from Bundesliga teams too - but not to systematically drive them out of competition, unlike Bayern, who have a recurring scheme here. Götze and probably Lewa are a part of this scheme.
2. Klopp is a mindgame specialist, at least equal to Mourinho. Comparing him with Hoeneß though is not going to happen, because at no point did Klopp try to destroy careers, much unlike Hoeneß. Google what he did to Willi Lemke, to Christoph Daum or the referee Helmut Krug or to the management of 1860 München for that matter.