They may have wanted or even craved meat, but they didn't "need" it because they were suffering from protein deficiency.
They had corn and beans which together make an excellent complete protein. Human meat was an elite monopoly, used more as a status symbol than anything else.
Many millions of people have gone their entire lives without eating meat. It isn't needed. (Although I like it a lot.)
Interesting post (#42). I accept your criticism of the word "need." It has been many years since I read Marvin Harris, but I think that he (or someone else) indicated that the Aztec agriculture was inadequate. I "need" to revisit the research..... Relavent in a way now since the professors of Aztlan want to revisit [sic] their paradise on California etc.
Actually, you need beans, maize and squash - and if you had a bad harvest on any of 'em, or otherwise couldn't get all three, you were in bad shape.
Human meat was a luxury item, reserved for the upper class, and commoners could advance in rank by capturing it for 'em....
Thank goodness for Cortez.