Yes but you do not gain anything just buying weapons. If you don't have the soldiers to use them, then they are useless.
If you buy 10 Bows with power of 40 you get 400 extra points. If you buy 10 swords at 20 power you only get 200 extra offensive points.
If you buy 50 swords and still only have 10 soldiers you still only get 200 extra offensive points. Cause you only use the same amount of weapons vs soldiers.
Buying extra does nothing but stockpile said weapon or armor.