If you start from successful startups, you find they often behaved like nonprofits. And if you start from ideas for nonprofits, you find they'd often make good startups.
In Under the Radar, where I argued in favor of bootstrapping a business, I wrote
Fundraising is not for businesses. Fundraising is for charities.
I was so proud of that line that I used it twice in the same book.
In a sense, seeing similarities between businesses and charities is not terribly profound. It takes a certain amount of benevolence (concern for customers and employees, for example) to be successful in business. It takes a certain amount of financial discipline to run a successful charity.