A lot of the subtly gets lost in translation from the French, the song just doesn't work as well in English.
Yes, it's not quite as bad as the translation of Le Moribond but you're absolutely right. It's Mort Schuman's translations - he either wasn't able or didn't bother trying to capture the nuances or the poetry of Brel's lyrics.
Compare and contrast Jake Thackray's Brother Gorilla, an interpretation of George Brassens' Le Gorille that captures the spirit of the original perfectly and has humour and poetry all of its own.
Going off on a slight tangent here, but I'm reminded of the Asterix books - the punning character names are actually funnier in the English translations than in the French originals.
d.