[m_fayer]

Rational or not, it's somehow creepier when an OS is doing it, as opposed to most of the crunching being done on Google's servers.

If you have any feeling at all for how an OS operates, Windows 10 with default settings has the air of someone creepily muttering to themselves and fidgeting with something under the table (half the time some component is eating 20% of the CPU). Then the second you walk away they spring up and maniacally run into a closet and commence making mysterious banging noises (walk away and some component spins up to 100% CPU and stays there, fans commence howling). You walk back into the room and there they are - sitting, red, panting, comically failing at looking nonchalant. It's a unique combination of creepy and comical, all in all.

Whereas with Google docs, you really have to know what you're looking for to see manifestations of all the tracking, though of course that doesn't make it better.