If they had used the english words, I wouldn't even have raised a eyebrow.
The German words "Blut und Ehre" are NOT just only the two words Blood & Honor. Their meaning is beyond their english counterparts, meaning something different.
(Just like the word "liberal" is the translation of the German word "Liberal" - but it has in reality a completely different political connotation in the USA than in Europe)
It's a fixed term in the German language ONLY used to depict nazi ideology. Actually it's describing it's very most core. It's not only the Hitler Youth motto, but was introduced as a "judicial "concept" in the Nurenberg Laws in 1935, which denaturalized the German Jews and was the base for any racial discrimination in the Third Reich. Actually the central part was the "Gesetz zum Schutze des deutschen Blutes und der deutschen Ehre" -"The Law for the Protection of German Blood and German Honour". There are few terms linked as closely to that ideology as this one. You instantly connect this term with National Socialism & Holocaust.
It's easy for an American to see only two foreign words there - It's about impossible for a German that actually speaks that language.