Money is a motivator. In a good way, I think. Most of us need to earn money to pay our bills and fulfil our obligations, and it is the prospect of being able to do this that often drives us forward and motivates us in our work. Those of us who are, for better or worse, operating with the capitalist framework.
Which is to say that other people's vanity projects are actually not a good platform for anyone (whether creative, entrepreneur, labourer, etc.) to be working for free because what is the motivation to work if not to be paid? For the opportunity to increase the value of someone else's vanity project? Not likely. Not me. There is of course work to be done for money, and to create opportunities to earn money. Then, there is work that many of us will do out of love, in one form or another. It's easy to forget but important to remember the difference.