I have no problem with the shopping lens... although I turn it off myself.
But look for a second at anything similar from any large successful company, and you'll see that on install you are notified of what the software sends back and given a choice ... not opt-in or opt-out so much as a direct decision. Why? Lawsuits, that's why.
Making the shopping lens on by default, not notifying users, and having it difficult for a novice to disable are a perfect trifecta to open yourself up to legal action, and I certainly don't want to see that happen.