Bunuel films that aren't about the upper class or religion?

His last two films are less about those themes than the ones you mention. "The Phantom of Liberty" is a hodgepodge of different topics--- if you can figure out what it's "about", write a book about it and let the world know--- and "That Obscure Object of Desire" is more about obsession than anything else. The main character is upper class but that isn't the aspect of him that's really made fun of.

Part of me wants to say it's simplistic to summarize Bunuel by saying he "doesn't like" rich people or religion. For me, I think it's mainly that he loves the topic of repression (particularly repressed desire). He likes to satirize it, and I he's probably also turned on by it. So it's natural for him to focus on characters that are really restricted in how they behave in public. Poorer people and people who are less religious are generally less inhibited, so to him they are probably less interesting. Is he the world's biggest fan of wealthy people or Catholicism, definitely not--- but I that's more of a side effect of what he's trying to get across, than what he's trying to get across.

On the other hand, I completely get what you are saying. Frankly I don't really like Bunuel for his thematic focus--- particularly earlier Bunuel, when he was more obvious about it (stay well away from L'Age d'Or). I like "The Discreet Charm of the Bourgeoisie" mainly because of the tons of absurdity he crams into the plot. "The Exterminating Angel", which as you say is quite similar, I find almost unwatchable. It's like *I'm* stuck in that house, forced to sit there while Bunuel runs over the same points that I got in the first 10 minutes. (I have the same problem with essentially every play by Bertolt Brecht.)