[brandon272]

This point of view assumes that the injected code is harmless and never causes compatibility issues when viewing a website. The moment a JavaScript conflict occurs and Apple loses a sale or the ability to buy a product online is hindered, I think that there will be parties who certainly feel they are being "harmed" by this process of manipulating the content being delivered to end users.

[iy56]

Yes, this technique could potentially be misused. You can say the same thing about any technology.