I'm not familiar with Luxembourg's oil activity, but I highly doubt it. I know that the country has had coal mines. To give you an idea of the scale, let's say that Luxembourg's population roughly aligns with the city of Gatineau's population, or with the slightly larger populations of Laval or Longueuil. The territory is quite small. While the economy is in fact booming, the population is small. Luxembourg is probably one of the richest countries in the world, per capita. However, this isn't necessarily the result of booming tangible economic activity.
I suspect that many transactions to and from this country are taking place because of a well-known fact. Luxembourg is often referred to as a “country of post office boxes.” Companies have addresses that consist of an office shared by several companies or that are limited to a single post office box. This situation is very common because Luxembourg is a tax-friendly country. That's the justification.
Mr. Mahabir can elaborate on this topic.