I distinctly remember games where they provided stats for “females and children”,sometimes by referring to another monster like “treat Orc children as Goblins” or similar.
so at least in some games I was a part of, errant (or fir done players well placed) Fireballs/Cloudkills could rack up additional XP.
Yes. That was done in later editions, 3e, I think.
But way back in "Keep on the Borderlands," Gygax decided to make orcs, goblins, kobolds and all the rest breed just like any normal race, so he put in orc female and whelp "noncombatants," thus confronting the earliest D&D players with the problem. Of course, Gary didn't realize it
was a problem, and assumed that given a medieval justice mindset, it would be fine to just kill them all. And that somehow, this isn't inconsistent with the concept of metaphysical good. Ooo-kay. Sure. That's his viewpoint, but I disagree.
That's the tricky thing when it comes to playing in a world informed by history. Historically, raiding parties, and armies tended to view "the enemy" as combatants to be dispatched. Yes, that includes civilians. Look at all the historical examples of towns being looted, pillaged and worse by advancing armies. Knights and others had the right of High Justice, which meant they could punish people as they saw fit. Some of this is tied to the relative lack of prisons, so justice was often swift and violent (executions and mutilation were common punishments). People could do all of these things without pause and still think of themselves as "good," and yes, that should make our modern sensibilities wince.
We look back on those times from a modern perspective and admire the legendary Robin Hood, who opposed the Sheriff's excessive taxes and too-severe High Justice, and was outlawed for it. Does that mean we think that thievery is fine? No, but it means that to a modern mindset, maybe you shouldn't have your hand chopped off for poaching because you're starving. And it's pretty disingenuous to talk about "medieval justice" and morality and simply gloss over the legend of Robin Hood.
But how does that play out in a world where Good and Evil are actually cosmic forces? If the practical medieval combatant commits evil acts to maintain order, has he behaved in a way that the gods of Good will punish him? It's actually
less problematic when you talk about Law & Chaos, because the terms are less loaded. Which makes me wonder if that is the reason Moorcock opted for the latter in his Elric saga. One of the biggest problems with alignment, is that the DM's personal sensibilities become the cosmic law of the universe.
Personally, I tend to take the attitude that "mercy is a hallmark of good" and "keeping your word is a hallmark of law," ergo if you're good and/or lawful, there are times you don't kill non-combatants. A lawful good character would not only not kill innocents (that's the good part), they wouldn't kill combatants who had surrendered (that's the lawful part). In my mind, it's just as evil to kill orc whelps as it is to summarily dispatch all the children when you finally bring down Evil Kingdom #6.
Ultimately, talk it out with your group. Figure out what level of moral quandary you want to have in your medieval fantasy (or other) game, and make sure that all parties are on the same page. Some games handle this pretty smoothly, with things like "Keeps his word," "Won't kill prisoners or the defenseless," or the like available as a game hindrance.