I didn't say it's not true, just wanted to point that if it is then some response to these topics might help.
Actually I am not that concerned about anyone stealing the credentials to my favourite restaurant's website (I don't keep sensitive data in these programs), but nevertheless I am doing my homework in form of a "security audit". I am no security expert nor have access to the source code, but can still find the obvious things (database, encryption, cloud sync, communication, etc) which might make people a little bit less afraid of your software.
Even then, these days it's quite common that people are afraid of anything when it comes to their privacy. This is something that you should keep in mind when choosing not to do a third-party audit because <insert any reason here>.