[mechanical_fish]

You certainly can make a lot of money by building useful non-social software. It just wont be as visible or talked about.

Precisely. The original submitter's friend is thinking one of two things, alone or in combination:

1. "If I take this useful app and add some social networking, it will help to market itself, which means it will sell more copies faster. Maybe it will even go viral and I can quit my day job!"

2. "Given the choice between building an app that is useful but obscure and being visible and talked about, I'd rather be notorious."

Point 1 is sometimes right, but often wrong. There are lots of tools that require a more traditional style of sales and marketing... and that have no use for tacked-on social networking features.

Point 2, while not exactly wrong, is a different objective than simply making money or improving people's lives.