:

It seems like the consensus is that I
should use vapor barrier. However, I haven't received any good
arguments for other than the reason I mentioned.

The insulation will minimize the heat differential between the concrete
walls and the conditioned air space inside helping to prevent condensation
on the walls. The vapor barrier will keep the moisture inside further
preventing condensation on the concrete wall. Ever walk outside in the
morning and see dew or frost on your car windshield? The windshield is a
vapor barrier keeping the condensation outside, rather than inside.

If you are having moisture problems from outside then do not use
fiberglass insulation, use rigid foam.
--
Mac Cool