Getting past the concept that everything is 'obviously an object of great religious significance' and recognizing that much was, indeed, everyday technology, utilized for more plebian purpose related to everyday life is the biggest hurdle cultural anthropologists face. Recognizing at a visceral level that these were people, motivated by all the basic motivations which persist in human nature is key to understanding the past.
Our technology, dress, language, and many superficialities have changed, but the same basic motives persist, with the same emotions, the same fundamental needs and desires which continue to push individuals and societies to do what they do with the resources available to them. Looking beyond that, we find that even the greatest of these civilizations fell prey to problems internal, external, or beyond their control, and the real lessons to be learned are in where they met their demise.