Rushing cultural buildings also helps prevent flipping in recently conquered cities, and expands your city limits so you have more room for your workers. More terrain = better score too. Rushing a worker out of a conquered city will give you a slave, which in the long term save you a lot more than you'd pay to have him finished. You can also send more cash to entertainment and make more citizens happy. Unhappy citizens don't count for your score, and happy ones count double. And later, when I build the Int Agency, it gives me one of the most fun uses for gold: propaganda. I've flipped many cities to my side this way. It costs a lot, but by that time, I'll have more gold than I know what to do with it. So although gold doesn't count for score as itself, it has many uses that will improve your score.