Why is it , in Indian cooking, it's a good thing that the oils separate?

[carmeninthecupboard]

I've noticed a lot of dishes have an aim to separate the oils ( and the sit on top like a separate little sauce)
I know not every dish is like this and I'm are many cultures jave food with this attribute.

Why? It's a strange concept to me (a lot of oil turns my stomach)

[JQuick]

Oil on top can act as a short term preservative that holds the moisture in and keeps the oxygen and air out. A lot of traditional recipes were developed long before refrigeration (or antibiotics) existed, when food preservation was a matter of life or death on a daily basis. Many kinds of foods and drinks we enjoy today came about to reduce spoilage and contamination. Other examples are beer, beer hops, wine and alcohols, salting, candying/sugaring, dehydrating/drying, and spicing. Many spices have antibacterial properties.