We have stickers for stores to put on their doors so you know if they're using Density. We don't want to be sneaky about this.

Stores will have a strong incentive not to advertise that they're using your service, as Nordstrom found out. Will you be doing anything to check whether stores post the stickers properly? Will you terminate service if they don't?

Euclid Analytics keeps their customers secret, so if a store doesn't post notices, there's no way for us to know they're using the service. Will you be keeping your customers secret as well?

Spoof your MAC address, use airplane mode, there's other ways I'm sure.

Agreed, this seems invasive and I dislike it.