For example, I am fulfilled by aesthetic pursuits like painting, writing music, and performance literature. I don't fool myself into thinking I am good enough at any of these things to make money off of them. But it's no less fulfilling than the kinds of risks one would take in business. In fact, I'd argue it's more fulfilling to artistically express something about your core self and then put it on display. This is with my impression (from stories on HN) that the startup world can be very superficial.
The point is fulfillment and risk come in many shapes and sizes. You don't have to risk your family's welfare and work 55 hour weeks to get valuable life experiences. Maybe you need it to develop flawless business acumen, but the OP is pretty clearly talking about life experience here.