>It seems that when it comes to weapons, there's a
>disproportionate distribution.

They are available in the proportion of classes that can use them. This means staff/spear/polearm/whip/flail are not as common as sword/mace/dagger.

>Swords, maces, axes, and daggers are available in profusion,
>while staves, spears, polearms, whips, and flails are
>exceedingly rare.
>
>While of course swords are the most common weapon, there seems
>to be a much larger discrepancy than there should be. Am I
>alone in thinking this?

And the formulas used for limiting these items take that into account. I don't see any problems with the amount of any of these weapons.