Probably because it's a just-so story not based on reality. Building a career and finding a mate surely must be more influenced by the breadth of your social network than is your ability to help your children and grandchildren. Think about how many people you know who have gotten jobs or met their significant others through friends or acquaintances. I think anyone who sees interactions with strangers as adversarial should take a closer look at why their own stance is so suspicious. Getting to know new people definitely isn't easy, but it's incredibly rewarding in itself and opens so many doors.

I said it was a fantastic insight. I didn't say it was right. :)

Actually, I think you're both right. The idea that young adults should be suspicious and selfish is limiting and wrong. But the idea that older adults have different motivations socially is spot-on. In part, even the introverts and misanthropes have learned to value just talking to people, eventually.