This might be a question for /r/askculinary, where there's another good question about high brow/low brow ethnic food.

I'm sure both classes of food workers have co-existed for a while, and it has to do with the cost/value of food and techniques. Food today can be seen as a valued art form or a necessary commodity

There might be different answers to your question but i can offer a perspective from Europe. One way of looking at this is to see food as being valued as a form of "connoisseurship".

Initially, food was tied largely with health. Most of the time, people ate because the Galenic system told them what they should eat with regards to how the food tasted. The 17th and 18th century period was a period of the Galenic medicine gave way to a more modern standard of understanding health and therefore a delineation from the humoural system. Hence, people could start eating, not as a dietary corrective and people could explore cooking to flatter tastes. This was a period where the Dutch began to dominate the spice trade and therefore the cost of spice decreased and it reached a point where people began to own their own small gardens. As such, there was now a

Another interesting development would be the emergence of celebrity chefs. Chefs such as La Varenne (Le Cuisinier françois) and Nicholas de Bonnefons (Les delices de la campagne) began writing cookbooks which contains intricate recipes detailing the way food should be cooked. The proliferation of the upper class and their desire for tasting good food therefore starts this auto catalytic process.

Source: Pinknard, S. "Foundations of Change: 1600-1650" in A Revolution in Taste.