Even though he wasn't accepting money from his parents, he was implicitly using their financial security to shoulder this risk. If everything had really gone to hell, they would have helped him back on his feet. (Much like some banks could take huge risks knowing the government would probably bail them out, even if there wasn't an explicit agreement or exchange of money beforehand.) Other people, like maybe his friend, don't have such a financial safety net and so can't take on those kinds of risks.