It's a cheap oil in Asia due to a bunch of countries trying to develop their agriculture by planting palm (Indonesia etc.)
Makes me think twice about having yan yan snacks and pocky's.
The reason why palm oil is so widespread nowadays is because about 30 years ago it was widely promoted as THE best oil to grow - it has much higher yield than many other oils, and was seen as a "green" alternative since comparatively it takes less land than say, peanut oil.
The problem is that yes, it takes less land, but the land that it can be suitably grown on is very important for other things.
To be fair, so is much of our other land, but we have the excuse that we already destroyed it many years ago.