No, I just didn't think the second part negated the first part. I read it as the defense being to some degree legitimate, but that he was doing so out of self-interest. I was trying to underscore how absurd his so-called defense was.
In other words, my apologies! I didn't intend for my attempt at an explanation as criticism of you, or start some pointless quibbling internet argument (because I imagine we're all tired of those). Take care out there.
Minotaurs, if anything like their brahman brethren, can get nutrition from all kinds of roughage that us puny primates can't. So while we're scrambling around for nuts and goodberries, they can make a meal of all the weeds sprouting in terrible soil, and the odd hay bale lying around to feed someone's horses.
TL;DR: They could feasibly turn what we consider indigestible garbage-plants into calorie-rich milk.