I was younger and stupid.
Nah, let me walk you through my thought process.
I was working on a template for a more realistic top down game. The dude wanted super-realistic every-blade-of-grass style art. I was fresh off my first month dabbling in anatomy, so I went out of my way and did something I normally would not have done - made a musclebaby. Had it been my call, I would have made everything like the last image, probably something even more simplified and cartoony. So I flexed my muscles and gave him something I interpreted as "realistic". Then I went through further simplification and fought with the project leader until I did that last image. (upon return from a lengthy hiatus of working on it, I learned much about what I considered tasteful and distasteful in my own eyes, and made changes accordingly.)
I think it's the same driving force behind people drawing beefy men when they practice anatomy. I mean, there's some intrinsic pull to draw bulging muscles. I've felt it before, but I've not exactly liked the outcome. I find people with huge muscles to be kind of creepy personally, but it's a very interesting thing to explore because of the sheer power the image of muscles hold over humans.
Of course, that's not why I made those sprites so beefy. I was being plain ignorant of what I was making and how ugly it was. Besides the poor craftsmanship, of course.