Banknote with a real wax (or wax-like) seal attached?

Hello,

 I have recently seen this banknote  N#226452 with real wax seal attached to it. The seal was some variant of the German eagle I was wondering if that is some real historical act done for a reason?

Pictures?

Front

Back
 

I think this is a sticker for attaching banknotes to an album. You'll find these on many German banknotes.