Propane bottle exchange, a target for thieves?

We do as suggested above and pay first before bringing propane tank out to do exchange, I guess no matter where you are, when someone is desperate enough anything is subject to being stolen. We don't do propane tanks exchanges too often but the need has presented itself a few times over the last decade. When we do we don't over think the minuscule few dollars we could have saved, it is simply a matter of convenience, we certainly wouldn't be RVing if that was the case.