I agree with this theory. People tend to buy more apps because they don't know "which tool" will solve their problem. I have done this at least 15 times this year, bought multiple apps to solve a particular task and then realized that there was another app that probably would have been better.

Chalk that up to the era of disposable apps -- Spending a few bucks during discovery doesn't seem like such a bad thing to a user, I guess, but in aggregate, is pretty unsatisfying.