German suddenly makes Esperanto make sense

As you know, I'm learning German and dabbling in Esperanto. Esperanto is primarily based on romance languages as far as the vocabulary goes, with a bit of English and German thrown in, and its cases are a bit like German. One thing that was bugging me about Esperanto was that when I learnt about subordinate clauses, there was always a comma after the main verb. Like this:

I hope, that I get something nice for Xmas. 

This is weird to me, as it's just not the way we do it in English and I can't help reading it with a strange Shatneresque style. But I have discovered that German does this (romance languages do not, at least in my experience), so it appears to be another aspect of Esperanto borrowed from German rather than the romance languages.