At first I would think the couples are the same.
I can't ignore your thoughts about the different dates but there could be another reason. I think the church book entries were transcribed for the civil records.
The Palatinate became part of the Bavarian Kingdom after the Napoleonic Wars.
(see link) http://en.wikipedia.org/wiki/Palatinate_(region
Perhaps there were mistakes made by the clerk. Also mistakes could be done by transcribing the filmed documents. To be sure, you have to go to the "basement" of your LDS center and read the films. Maybe you'll find remarks or annotations
of the minister (priest).
I found another IGI record for Anna Regina Kappner (see attached screen shot).
With the names of her parents you'll find more information at FAMILYSEARCH.ORG.
Best wishes from Germany,