Hyperbole.. dear lord - over exaggeration.
* use your favourite mac listing website of your choice - you only need to find a few, and they don't take long to find. Only need to do this once.
* Pretty much all companies allow you to re-download, so no need to worry there.
* a lot of software listing sites allow reviews, for example, mac update, versiontracker
* most software companies use reputable payment processors, larger companies often use their own - and can be trusted.
* UNLIKE, the mac appstore, you can very often download TRIAL versions so you can TRY BEFORE you BUY!
Sure, the mac app store is convenient, but shouldn't be relied upon as the only source of software due to its limitations and limited software listings.
If someone never ventures out side the appstore then they'll miss out on gems such as 1Password, Launchbar, bettertouchtool... and many others.