This quote is suggesting that art for art’s sake is something that only people who are financially secure can realistically pursue. It implies that art for art’s own sake is a luxury, not a necessity. This means that those who can’t afford art or the time to pursue it are not able to think of it as anything more than just a hobby or an indulgence. The phrase “well-fed” implies that these people have the resources to create art without needing to worry about financial security.