These four guys just had no idea what was about to happen to them. The young men in the picture are Michael Lang, Artie Kornfield (great name for a festival organizer), John P. Roberts and Joel Rosenman. It was the latter two in particular who invested the money to make the event happen. They probably hoped that a good crowd would turn up and things would go swimmingly. They underestimated the public's appetite.
The four were business partners, and actually just wanted to stage a festival to promote their own music studio. They had almost no relevant experience and were completely out of their depth; aside from the rush to the bank, the failure to sell tickets and the venue changing three times, they didn't do anything about building a stage until less than a month before the festival happened. Everything was done last minute in a rush, with fingers crossed and prayers whispered.