Define 'just enough to get by'.
Even if investors and employees are in it for a higher altruistic goal, they'll still want a good return on their time and money. Very few people are wont to just burn money so that someone else gets to enjoy playing CEO of a cool company. And even if they do enjoy it for a couple of years, the fun will soon stop.
Profit has to be the main motive for any long-term, successful enterprise. And the really big goals require really long periods of profitability to keep everyone interested and invested, whether with their money or their time.