We almost always lose our stuff in places where people want to return the item: the gym, office, school, university, restaurants, taxi's, cafe's, airports, train stations. None of these places want to keep hold of your stuff, they'd much rather you come back as a happy friend & customer, just currently there is no easy way for them to return an item to you.
Outside of these places, say at a random park, the kindness economy truly exists and the high majority of people look to return items if possible. A BoomerangTag® makes a previously impossible return, possible.