I'd rather teach how to earn money in an enjoyable way. "This is work, it's unpleasant but it earns you money and keeps you alive and we all do it because we have to" is not really the message I want to convey.
I think there will be enough opportunities for the kid to learn about having to work (like household chores, school homework).
And actually even setting up for enjoyable work will probably have some less enjoyable aspects.
And also, creating your own business isn't easy.