Sure without money you can donate time, but I will argue that a large monetary endowment does way more than filling soup bowls an hour a week.

Typically how large private equity funds work is, they will raise funds (in the billions of dollars), from institutions (limited partners, like endowments, pensions, UHNW, etc) who write very large checks.

For instances the largest owners or funders of Timber Deeds and or Timber land in the pac nor west is John Hancock and the Harvard endowment fund..

I highly recommend researching David Swensen from Yale and the Endowment Model. 

So if you are a good enough salesperson to convince an Ivy League endowment, a family office, or a sovereign wealth fund to invest....well you make something even if you're a loser. 

He is Regents Professor, McKnight Presidential Endowed Chair in Public Health, the director of the Center for Infectious Disease Research and Policy (CIDRAP), Distinguished Teaching Professor in the Division of Environmental Health Sciences, School of Public Health, a professor in the Technological Leadership Institute, College of Science and Engineering, and an adjunct professor in the Medical School, all at the University of Minnesota.