I am not so sure, if this "german are no refugees" is not a simple prejudice. This is for sure against the public tradition. But according to this article, there were about 12-14 million german refugee between 1944 and 1950 in europe:
https://de.wikipedia.org/wiki/Flucht_und_Vertreibung_Deutscher_aus_Mittel-_und_Osteuropa_1945%E2%80%931950
Indeed, the percentage of the refugees to the complete population is lower, than the one in syria. But for me it is comprehensible. I think, one important point is the belief in the way what the government is. E.g. most people i know from ukraine, believe that their government is group of criminal mafiosi behaving like kings with working slaves. They believe that industrial people, mafia and government are all the same, and the normal citizen will never benefit from their decisions. So the connection between the citizen and government is close to zero. E.g. in my opinion the german government is strongly influenced by industrial people but these people are not identical in person and normally they are normally not mafiosi. So, i really believe that the government is really interested in the wealth of their citizen. This would be an important factor if you believe that you trust your government or not. And of course, how to react when they say you have to fight for the country. I am not sure how it is in syria. I can believe that it is very complicated and some mixture between these two extremes.