That $3 iOS app or $6 web service may or may not be entirely useless to you; it's quite difficult to know.
I mean, it's easy to make sarcastic quips about the mentality. But there are good, clear reasons why it exists. And if you understand them, maybe you can do something about it - make it very clear exactly what your app does, include informative screenshots, offer a demo version, make payment easy, etc.