I have to say, my startup has struggled with this. We're a two-man shop, and neither of us buys phone apps, pays for virtual goods, clicks on ads, etc. It tends to make us think that other people don't do those things either, despite the overwhelming evidence to the contrary.

Part of the article's conclusion is, "Get the product in front of your core audience," and I suspect that's the only way for the inexperienced to accurately gauge the value of their product.