Oh, so we're doing a thing where the demographics for this thread's hypothetical army are completely different than the assumptions in the DMG?
Regardless, it's still stupid to regularly use 1st-level wizards, especially human wizards, as army cannon fodder even if they're as common as commoners. D&D Wizards, unlike real-world soldiers, have a high ceiling for growth. The difference in efficacy between a seasoned infantryman veteran that has gone to several training billets/schools and someone fresh out of boot camp in the real world isn't super-duper high. Wizards, of course, are quadratic in power, such that a force of 100 5th-level wizards will roflstomp a force of 1000 1st-level wizards. You thus only field 1st-level wizards if you can't keep them in reserve and training, such as if you're being besieged
right now.
Shady314 wrote:Because their biggest value is probably activating arcane scrolls and wands 100% reliably.
Activating arcane scrolls and wands is, military speaking, a waste of money most of the time. A wand of fireballs costs over 10,000 gp and isn't appreciably better in efficiency, availability, or efficacy in the vast majority of military instances than spending a a year training 30 warriors to 2nd or 3rd level and equipping them with shortbows. And that's one of the better wands.