Ships are in the vicinity of Mauritius because "Mauritius and the nearby island of Reunion lie on the shortest straight-line route between the Strait of Malacca, which links the ports of Asia to the Indian Ocean, and the southern tip of Africa." Mauritius seems not to have "put in place a safety zone". These seem at least part of the picture.

https://gcaptain.com/heres-why-so-much-world-trade-passes-ma...

I think this is probably to cut distances and save on fuel and time. The reefs' safety is completely disregarded it seems. But we should know that already, these companies don't care much about the environment, they only do when they have to make large payouts to fix the damages.

Not to minimize it, but you seem to be only thinking about this one instance of a sunk tanker, and not the thousands and thousands of ships that do this on a regular basis with no problem. These low probability risks, and countless others like them, are part of a tapestry of a probabilistic horror show that supports our everyday way of life.

To shorten the route and save a buck probably.

Profit