What those who poo-poo the nay-sayers on such matters as this fail to realize is that TRUST IS EARNED.
And trust that's been violated...especially REPEATEDLY...is not easily regained.
Government and private industry have repeatedly demonstrated a complete lack of respect for privacy concerns, most especially in modern times since the advent of computers, phones, and data networks like the internet and whatnot.
Government sanctioned spying (of which the PATRIOT ACT is but one example), spying on political candidates, corporations tracking/buying/selling/trading in personal information, failure to adequately protect people's data/information, failure to stand up and notify people promptly for data breaches, making it difficult for people to recover their assets/lives when such thefts happen under their watch, etc.
Every day we hear about such examples. And the legal excuse for these people in many cases basically amounts to "well, there's no law AGAINST this...".
In other words "We'll give it to you up the pooper and there's nothing you can do about it."
Add to this the fact that since a LOT of this is in the tech industry where consumers literally cannot see, or know, how the software actually works, this means the consumers DON'T HAVE ANY WAY OF REALLY KNOWING WHAT OR HOW SUCH THINGS ACTUALLY WORK.
SO...is it really any surprise when a company comes out with a tracking app, saying "it's all on your phone, no information is ONLY locally generated and transmitted between nearby phones with the app and not servers tracking your every move" that most people are saying "Oh, reeeeeeally, now? I don't believe you."