In this situation, the privacy violation of becoming a suspect via location history is an utterly negligible problem. What you describe could just as easily happen in a traffic stop (and in fact probably far more likely).

> could just as easily happen in a traffic stop

Well it clearly does....

But I think the point being made is that part of the issue is lazy policing/detective work. The concern about privacy is really about the concern of __abuse__ of data. Why many of us want to protect our data is that we do not trust those in power, nor current nor potential future rulers (a big concern). Such instances as the above example are abuse of that data, as well as abuse of power. The thought is that if they are going to abuse us, we're going to make it more difficult. Dragnet operations make the above easier, not the same level of difficulty.