The two most despicable characters in Don Quixote

Can there be any doubt that the duke and duchess (unnamed, as far as I can tell, much like Sancho Panza's donkey) are the two most despicable characters in Miguel de Cervantes's "Don Quixote"? I thought we were pretty much rid of these snobs and louts, but, no, as DQ works his way home, defeated, beaten, depressed, and humiliated, the send out their thugs to grab DQ and SP and divert them, bring them into the castle, where they are once again subjected to harassment humiliation and, in SP's case, two some physical abuse. Oh, what fun it must be for these two members of the so-called nobility to torment someone who is obviously weak and mentally disturbed! I don't know anything about the history of criticism of Don Quixote, but I sure hope that this has been remarked upon by all readers - and I hope readers and critics don't write this off as "irony": how "ironic" it is that the unlettered SP and the simple DQ behave with greater nobility than the aristocrats, and so forth - no, it's not "irony" - what Cervantes is showing here is the true conflict of class relations, one class contributing nothing to the good of society, totally undeserving of its privileges, which it holds onto through force and intimidation, and exploiting in every possible way the class that is "below" it: this is a system bound to implode, and in fact was beginning to do so in Cervantes's time. He saw through the contradictions of his era, and captured this in his great novel. Have others seen this as well? I hope so.