App store updates, remove functionality: Unethical business practices?

First it was Pandora Radio-app include annoying audio advertising in one APP store update. Then, after upgrading the SHAZAM this last summer I learned app recently that the app is now obsolete after five (per month) and forces you to pay $5 and update to restore its functionality. I think that is what you get as an "early adopter".

In General, if you think an update are expecting you features to your apps added. Occasionally, but corporations are apps remove update – rather than add - functionality of apps.

I expect that some people say the company has the right to do what you want, especially because it's a free app. I agree. Is however, this sound business practice? It is certainly a great way to piss off - or at least annoy - your most loyal users.

It is the classical loss selling trick - you advertise the product as free and unlimited, then swipe your privileges away and force to get the features, you enjoyed for free to pay. As a user in a Forum Thread about the question asked, "how white I requiring I no longer to your product in the future use to keep numbers?"

In a TechCrunch strategist David Dalka criticized post this same type of behavior among social networks digital business yesterday:

It's time for the Web community to stand up and scream that you are sick and tired of the constant terms of service changes, changes of privacy, steps backward in usability, affecting our mutual experience, comfort level with the sites we use and our enjoyment of the Web.

As social networks increasingly take advantage of users with constant terms of service changes, APP store app makers do the same. Sure, nobody will take these companies operating licenses, but it is a good way to hurt the image of the brand.

What do you think? Is unethical behavior? If app maker show more respect to their "early adopters", or are perfectly entitled, the proverbial carpet under your users feet with APP store pulling updates to remove the functionality?