Simple: server space and loading time. Any additions that slow the game down are to be avoided.

If you want a "soundtrack," might I suggest you go to Youtube and create your own playlist of WW2-era songs?

Here's a few suggested songs to include:

1. Panzerlied -- Germany



2. White Cliffs of Dover -- Britain



3. White Christmas -- United States



4. Lili Marlene -- Germany, Britain





5. Colonel Bogey March -- Britain



6. Hitler Has Only One Got Ball -- Britain



7. Boogie Woogie Bugle Boy -- United States



8. Scotland the Brave -- Britain



9. Der Fuehrer's Face -- United States



10. Erika -- Germany



11. The Navy Hymn -- Britain, United States



12. Der Koeniggraetzer Marsch