What? This is really dumb. Museums are extremely practical, just like schools: they educate people. Concert halls are for entertainment; they're just as useful as restaurants (after all, you could just eat microwave meals at home). Most public buildings have some kind of valid use that doesn't involve superstitious beliefs. Even medieval churches probably had some non-supernatural uses, I'm guessing, like being used as meeting halls or for public addresses. Egyptian pyramids had none of this: a few pharoahs' dead bodies were sealed away inside them along with lots of treasure, and that was it. Everyone else got dumped in a pit when they died.
Edit: I see your point now, that medieval churches had other functions besides the religious stuff. Still, I see those things as only secondary functions to the buildings; museums and concert halls have those things as their primary functions and are optimized for them. I've been in medieval churches, and there's very little artwork in them, relative to their size, compared to any decent art museum. But I agree, they were a lot more functional for the people of the time than the pyramids.