Not in the beginning. But after the industrial revolution it evolved into that. India was not only a source of raw material for the English, it was also a great market. The Brits wrecked the Indian textile industry, for example, then shipped Indian fiber to the UK where it was made into cloth which they then sold back to the Indians. The shipping costs, as well as the Navy to protect it, were funded by the English taxpayer. In China, they were faced with a nation that had no need for British goods, so they introduced opium and developed a market where none existed before. Tea, sugar, cacao, tobacco, spices, all non-essential luxuries, were brought from the colonies and sold in the metropole at a premium. The nations which provided these commodities, in turn, became addicted to the income from them and abandoned their own agricultural economies to provide them. The system fed on itself and grew into a grotesque parody of "a free market".

The purpose of economic imperialism isn't just to meet the needs of the mother country, it's to develop markets where there are none. Some of these markets are domestic, some in the colony, some in a third location (see Triangle Trade, the classic example and the Perfect Storm of greed). It is commerce for commerce's sake, the Paradise of the Middleman, and if it meets some human need as well that is only incidental.

Today, a whole new commodity market is being developed, human labor itself.