It being for sale means anyone can be doing it which might be a framing that would be more alarming to the law-and-order types.
But really you need a two prong solution:
1) restrict this from being collected and compiled in the first place, eliminate the ability to default to this tracking unless someone opts out
2) restrict the government's ability to use or acquire through non-market-based means. The claim here is that there's already restrictions on this vs directly surveiling, but I haven't seen directly which specific restrictions those are for buying off-the-shelf info and the article doesn't specify.
There are very really no companies that I trust to keep my data safe for 10, 20, 50 years. Leadership changes, ownership changes, etc. We have to cut it off at the source.
How about "more alarming to the lawmakers?"
Someone could show that movement info, for example, is available for sale on a legislator. Or a legislator's spouse or child.
Now do you see the problem, oh you who write the laws?
The entity that orchestrated that outing, with the accompanying simple purchase of location data, etc. was a Roman Catholic newspaper known for high-quality investigative pieces. https://www.pillarcatholic.com/p/pillar-investigates-usccb-g...
If such incriminating data is so easily procured against just one guy using a gay hookup app, imagine the treasure troves of data that could be wielded against Members of Congress and other people in power. Even in the absence of wrongdoing, I still don't think that public figures would enjoy having the public know their every move, every minute of every day, but the reality is that all the apps they run are phoning home and uploading that data constantly, unceasingly, and it's all for sale.