I love the idea, and it's just the kind of thing I'm paranoid enough to own, but the price is a bit up there. Hoping it comes down over time. But if I owned a restaurant, I'd be all over this, in a "Break Glass" kind of case.
They may eventually want to target individuals and those not in the high-risk area -- in which case the price will need to drop. However, for their current stage and what they're after it makes sense.
I've heard from an EMT friend that most choking deaths happen in restaurant bathrooms. Somebody gets up to excuse themselves to be polite and dies alone beside the dyson hand dryers.