That is their tradition so a part of their heritage, and they have the power to decide (via the park board) whether climbing Uluru should be allowed or not.
There are other examples, eg. some areas in India being exploited for mining/minerals, where traditional beliefs have been overruled - to the economic detriment of the locals.
Let's take an example closer to home. The presence of Stonehenge in it's current location is a major impediment to traffic and the economic prosperity of the SW. Why can't it be dug up and moved to a museum somewhere suitable?