Some of the 200 audience members are busy pushing social change as well. Arsen Ari Kalfayan, who by day runs business development for cloud labor start-up CrowdFlower (formerly called Dolores Labs), co-founded a nonprofit called Reason To Party that throws affordable fundraiser parties for a variety of causes, from an AIDS hospice to the San Francisco Food Bank. Kalfayan’s parties raise thousands of dollars from 20- and 30-somethings who normally couldn’t afford to attend the fancy black-tie fundraisers held by more traditional charities.