Do a simple tracker on a desktop, and people freak out. But all you have to do is change the form factor and UI metaphor to mobile and people are absolutely fine with constant location tracking, ambient sound being uploaded to the cloud (SIRI, etc.), a camera and a microphone that can be activated by all kinds of apps while the device is in your pocket, and a constant 24/7 Internet connection. You could never even approach that level of invasiveness on a desktop or laptop.
A desktop/laptop is a computer. A smartphone is a computer. Why the different reaction?
I wonder if it's a generation gap thing. Older people tend to use mobile devices less than younger people. Are the younger generation this oblivious?
Same phenomenon holds by the way with regard to jailed devices. Way back when Microsoft tried to introduce something called "trusted computing," which was basically just code signing. Everyone flipped the hell out and they shelved it. But mobile devices can't run software that isn't tethered to their app stores, and everyone is totally fine with that. Different form factor, different universe?
It also seems related to brand. When you sign into Chrome with your Google ID, Google tracks everything you do. But that's Google, not some random little foistware company, so that's okay I guess. Same goes for Safari and iCloud, etc.