On the up side, there are no support emails asking how to download and install such apps. This is especially true in the case of those that tend not to read published documentation and/or FAQs that address such questions before asking them.
On the down side, it's too easy to publicly judge and then dismiss an app. To a user, this might seem like a good thing, but to a developer it can be a headache... particularly when the user gives a relatively low rating due to the lack of a feature that is released only an hour or two later. In the case of the Android app store, a user has 24 hours to cancel an app purchase before their card is even charged... surely that's enough time to send an email to a developer and get a response back, especially if done during the week.
Interestingly enough, since adding said feature, not one purchase has been canceled.