Geeks are less willing to pay for a product or service, because their interest in new startups is largely a technical curiosity and/or a competitive curiosity. The people that are on the cutting-edge of technology are also constantly looking for the next thing, so they lose interest quickly. Non-geeks are much more likely to pay you and to continue paying you if your service actually helps them. An app is likely to be remarkable (in the literal sense) for geeks if it has a unique architecture or was written in an unusual language, etc., whereas an app can be very remarkable/viral among non-geeks as long as it is useful.
In sum: If you want a business, go after non-geeks. If you want 15 minutes of geek-fame, go after geeks.
Other companies either don't appeal to geeks or just aren't something a geek is likely to recommend in which case just targeting the general population is probably better.