I agree that once you own it, you have the right to do with it what you like. I have personally jail broken an iPod Touch and an iPhone to load Cydia on them back in the day and I believe I had the right to do so.

On the other hand you and I don’t have the right to dictate to Apple what software they write and what features it has. That includes features for installing and managing software packages, software upgrades, security features, etc.