Heh I suppose if nothing else the reason for having a locking gas cap is so that it can't come up missing
Because I agree on the siphoning, there's a ball-type vent inside most filler hoses that should block fuel from coming out the cap in case the car were to roll over, this has been a standard for some time and this also prevents any rubber or plastic lines intended for siphoning to get far enough down in there.
But I have locking caps myself, just for peace of mind.
As for drilling a hole that is stupid, more so because of the damage and the wasted fuel, there's no way a thief has enough container to hold whatever comes out so more than likely they steal a few gallons and the rest goes to waste...
Environmental hazards aside this bit of moronism makes the entire car useless...
If I were a judge I'd be for throwing the book at this kind of thief.
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