A couple of decades ago, at Springfield Ops, BLMF, an American (who ISTR was a frequent flyer) was accosted by a couple of the REME guys while parking his armoured HumVee up. Their requests for him to leave the keys with them so they could
have a cabbielook after it for him whilst he was away for a few hours were denied.
He made a great show of leaving the keys in the ignition and locking the doors with some very chunky security padlocks, boasting that there was no way they could get into it without busting the padlocks.
I think it took them less than a minute to source replacement split pins for the ones holding the cupola in place. They parked it back up facing the wrong way just so he would know it had been used.