.app packages are merely the binary with assets and a bunch of metadata for code signing, entitlements, icons and locales. If you "Show Package Contents" there's not much to them.
See also Paul Haddad's situation[1] (creator of TweetBot):
> I really want an official public statement. We have a large number of sub. renewals for year 3 of Tweetbot coming up in a couple of weeks. If we're permanently cut off I need to know so we can remove the app from sale and prevent those. Which obviously I'd rather not do.