I think this would be very hard, since there's no way to get the apps unless you pay via iTunes store. Sure, if someone already have d/l the app, maybe it could be added to installer but that would mean spending A LOT of money to get the apps in the first place. I doubt there is anyone who would do that. I dunno.
you shouldn't steal. . .but im sure there will eventually be a 'secret' source you can add to installer that will host all of the apps available in the App Store(both free and paid)
Stop being a d**k and pay the developers a wage for doing their job. It's like you going into work (you probably don't have a job) and your employer not paying you, ever.