I avoid plundering cause it feels like hacks. You can probably get more money from plundering then doing ANYTHING else. Even spawn camping their king for ransom.
Eh, I'm only doing it for WFaS. Generally, half of my battles end up with me getting hit by a bullet and taken prisoner, so having a way to quickly regain my army and equipment is a good thing. Especially since my captors are faster than me, so I get captured several times in a row, which means that I lose more than half my money and all a good chunk of my weapons.
If I were playing the orginal or warband, then I would agree with you. The other sources of income are good enough to rebuild your army for the odd time that you lose. And if you do become a prisoner, then you generally can outrun your captors when you escape, so you only lose a couple thousand denarii.
Not to mention never actually succeeding at sneaking into the town when you have any significant amount of renown, might as well just walk in fully armoured.
I always found sneaking into the towns to be lots of fun. By the time that I need to sneak into towns, I'd have enough armour that I could just tank the damage. Having to focus on blocking and dodging makes for a nice change of pace.