I believe the Aztecs ate the Anasazi.
Thanks for the link. It's certainly possible.
Alternatively, did you realize there were two separate cultures living in Chaco at the same time?
If you've been there, you're aware that, on one side of the draw, you have the so-called Great Houses -- Pueblo Bonito, et al. Structures of considerable scope...exhibiting exquisite engineering and alignment. These weren't drawn up on the back of a napkin, so to speak. Nor did they employ your brother-in-law for a contractor.
But, on the other side of the draw (or the tracks, one might say), are situated a group of hovels. Small, "single-family" dwellings, crudely constructed out of inferior materials. Likewise, their kivas were smaller and markedly less elaborate.
Unquestionably a caste system -- the upper crust...and the hired (or enslaved) help. The Chacoan and, as I recall, the McElmo cultures were co-existent.
Master and slave? Did the slaves revolt? Maybe they ate their masters?