It had surprised me when Lion came out that the installation was done by an "app", not as a bootable image. This is an unnecessary complication for those of us that need to maintain machines. Earlier, when updating a different machine, I had learned how painful this could be when the installation app destroyed the boot sector and I needed to reinstall Snow Leopard from DVD, and then upgrade that to a version of the s…
Also, Lion did actually come on an installable USB drive (which is more expensive than the App store Installer app). Not Mountain Lion though. Creating bootable disks (USB or DVD) from the installer app is trivial. Also his other point about losing all installers is actually a point in favor of the app store distribution model. They're always there unlike a physical disk which can go bad on you. Time machine and Migr…
You can be able to do something, and still find convienence in paying someone else to handle it for you.