Not even that. They have "crowd-sourced" location service of your items, meaning that each of their users acts like a scanner for all tracker devices out there. This is ripe for abuse.
What abuse? Apart from tagging valuable objects in a way that makes them easier to find. That let's someone could go through apparently deserted areas (like after a concert) and find valuables left behind.
But the actual privacy part shouldn't be too bad, right? They could use a time-based code, so that each beacon transmits a seemingly-random ID every minute, and only their servers can link that up to something.
If it's static, then yeah, it's like tagging yourself. Or carrying a modern passport. Or phone or laptop. It's a shame that most people will probably not really care about this aspect.
This is not like carrying a passport, phone or computer at all.
I can be tracked without my knowledge - somebody just needs to plant a minature tracker in my laptop bag.
Edit: The issue is that everybody tracks everybody, not like with Tile or Chipolo - where you only track your own tags with your own smartphone (ie: you need to be near your tagged items to track them, which makes covert location tracking of persons hard).
Eh, if that's the threat you're worried about, it's really just a race against time. For $15 you can already get a GSM+GPS "mini" (not micro) tracker. That was just a quick search. I'd be surprised if there are not smaller models already easily available.
Sure, a BLE beacon is gonna be easier to make small and power than a completely self-contained unit but it's not like this creates an entirely new threat.
1. Literally works for years compared to days.
2. Much smaller.
3. Works everywhere where people carry their phones (underground substructures impenetrable by GPS and GSM).
