[kelnos]

Agree with the sibling that people make insane gambles all the time.

But beyond that, I don't think your premise holds true. People do often start companies because they believe in (or even have a passion for) the thing their company will be doing. But people often just start companies because they believe those companies can make them money. That doesn't mean that the thing the company does is going to be good and sustainable over the longer term. Just that there's some money to be made, even if it's on the backs of speculators and gamblers that don't provide much value to the ecosystem.