Off-Hand Weapons

I never understood why a particular weapon is designated an "Off-Hand" weapon, since almost any weapon can be used in either hand. And, given the fact that the Off-Hand equipment is very rarely used, I don't understand why there is always so much of it available at the Blacksmith.

If I might make the suggestion: Eliminate the "Off-Hand" restriction, and simply allow a manager to choose which hand he wishes to equip with each weapon. Or, reduce the number of Off-Hand items available for sale at the shop. In a large number of cases, I have had to spend precious gold in order to find a weapon for sale which is not Off-Hand.

Increasing the Shield skill seems to increase the number of off-hand attacks, but the value of the off-hand weapons is still far less than that of a main hand weapon.