Based on the "End of the game" scoring example (and a couple other very specific references in the rule book), it appears the number in the top left corner of buildings and techniques is VP at end game.
I've really looked and can't find that explicitly stated, but since apparently nobody else asked here...maybe I've just missed it? Is that right?
On page 6 under "End of the game"it states "victory points indicated on buildings present in their neighbourhood".
Now it doesn't specifically say "at the top left corner" however, the font, colour and style of victory points numbers on cards throughout the game and board are all consistent. If it hasn't been asked, its because it's been understood as that. I would call that good graphic design. Without spelling it out, I'm guessing most players quickly understood that's what they are.
Also there are other examples and references like you mention.