What's the return on investment for supporting open source?

It's hard to be enthusiastic if you don't have a job that pays you enough and gives you enough free time in which to be enthusiastic. Enthusiasm is a luxury!

Even if people start out being enthusiastic when building open-source projects, they quickly lose the enthusiasm if when they are faced with an on-going choice between working for nothing and earning a living.

Most successful open-source software contributors have decently-paid jobs. The people who don't get paid enough are too busy struggling to earn a living to work for nothing on top of that.

That enthusiasm translates to a lot of very hard work, huge deployments and plenty of investment. What's wrong with enthusiasm?