At about $3000 (tax included) per 100 you could probably do more interesting things with say $10,000. Like giving stacks of 100 $1 bills to everyone around you except the people you want to piss off.
Right- I feel a Raspberry Pi and a bluetooth module (or a handful of them) would be a lot cheaper. Set it up to repeatedly ping everything in range, stick it to a battery pack, and just go about your business. It would certainly illustrate some of the many shortcomings of Bluetooth, and always-listening services.
I'm not advocating that you should, keep in mind. It certainly seems to be in poor taste, but there may be a platform for using it educationally, I.e. hacker cons.