Josh,
I will try to put aside my loyalty and bias and deal with the issues you mentioned.
Sunningdale Old doesn't have elephants buried under the greens. That's not the course. What is does have is some severely contoured greens which don't look to be as sloping as they actually are, along with some very confusing, subtle greens. Were you above the hole on 4? Were you to the left of the hole on 6? Were you anywhere left of the hole on 8? If you've experienced any of those putts, it's almost impossible to stop the ball short of the hole.
If the greens were that flat, I doubt Loren Roberts would, for the first time in his professional career, have had back to back three putts.
I'd be interested to know what you consider the "silly memorabilia and unnecessary nonsense" in the clubhouse. There's a room upstairs with books on all things golf related which is a lovely place to spend time. There is a Bobby Jones room with images from his career and famous round at Sunningdale. There is a picture of Walker Cuppers who were Members, and in the Visitors Changing room there are gifts donated by other fantastic golf clubs. There are historic images from tournaments played at Sunningdale of which the club is, rightly, in my opinion, proud. I've seen other golf clubs - Merion, Oakmont, Shinnecock, Cypress Point etc - all display similar exhibits. Personally I love it as it gives a feel for the history of a club.
I don't know if you were in the Members' Bar or not, but if not you might have been surrounded by a Society which might have given rise to your "spivvy" comment. I can assure you that the club is not trying to prove anything, to anyone.