Notice how you fought parties smaller than yours, where half of each party on their side was also recruits. That's perfectly fine, and I'm also attacking anyone I can catch up with or corner, but I'm mostly intercepting armies often twice my size that are trying to (re)conquer one of our towns/castles. Now due to my computer's (in)ability, I can only crank the max number of troops to 700 in the performance settings, and that means that, proportional to army size, I'm going to have around 250 troops at the start of battle to their 500. If many of my starting troops would happen to be recruits, it becomes difficult to fend off their waves without significant losses, and I need to have as few losses as possible, because right after this battle there's another one like it right around the corner and so on and so forth.
This all is mostly due to the frantic dynamic of wars and respawns.
Maybe if TW could achieve a more sane dynamic where, let's say, a 1000 vs 1000 battles would actually mean something and would happen like twice or trice a year at most, I wouldn't mind losing half my troops in such battles. The way it is now, since my AI fellow nobles are dumb as a doorbell, me and my army are a precious resource which should be treated as such and not wasted lightly.
I'm also playing on all max difficulties.
Anyway, I can only speak from my experience and voice my opinion. We all want this to transform into a great game so we could enjoy it more. How (and if) we get there, TW will have to decide.