I'm sure there's a term for the slight problem that someone who's good at a job usually wants to do it - the Praetorian Paradox maybe?
Albania, Andorra, Antigua and Barbuda, Argentina, Austria, Bahamas, Barbados, Belgium, Belize, Bhutan.
There's 10 countries, I'm not even out of the B's yet, and this is still skipping any country for which I think anyone might try to argue for the military's main focus to be to "loot and plunder other countries," not whether I agree with that assertion. Hell, I excluded armies whose main focus could arguably be to loot and plunder its own country rather than other countries (hi, Algeria).
And note that there a more countries on my list in this alphabet range than not on the list. Truly, there are more exceptions than examples to your proposed rule in the modern era, a very far cry from "there isn't one" indeed.
The Austrian military orients its war plans around the plunder of Austria - i.e. to minimize the damage of other militarys' plundering the nation.
There isn't any other purpose for a military than to manage this factor, either as aggressors or as defenders. Pillage and plunder is what militaries have always done, and prepared for ...
If you are going to say "but Iraq 2003!" I would ask you to consider the money we spent funding that expedition vs. the supposed financial gain. The reasons to invade weren't great, but looting and plundering were not among them.
The Syrian oil fields are an example of plunder. 1/3rd of Syria is occupied by Western forces - specifically its oil fields.
This resource is being intentionally withheld from the Syrian people, to prevent them from using the wealth to rebuild their country.
That is plunder.
And, the invasion of Iraq? That was nothing but utter destruction of a sovereign nation that was not willing to play Western ball.
Iraq lost 5% of its population to America's heinously evil war - that is human plunder, indeed.
Anyone who has attempted to wean the world off the petrodollar has found themselves deposed, assassinated, or otherwise eradicated from Western history.