Weighing the pro's and cons
A tractor--I fuel and fix when needed Housing optional
With a mule to match what a tractor can do---I can toss in about 4 mules per 10 HP needed,
so I need about 100 of them from time to time.. but not all the time of course. But I still need to keep on hand. Thus.....
I always have to feed, brush clean, make hay, feed hay, clean out fed hay, house in winter most of the time. Times the number of head required.
Yes the list is lopsided.

I did not toss in STUBBORN mules.