I imagine the same would apply to ferries, and capture every caravan and HV as well, I can't seriously imagine they would all be searched.
I don't think they're bothered, when we bought the motorhome back from travelling the thing was essentially a giant bomb on wheels with gas bottles from half a dozen different countries, a full tank of fuel, several cans of diesel, a couple of cans of petrol for the genny and enough alcohol to knock a legion out. When they searched it they didn't bat an eye.
I did say to Mrs S if we have a smash on the motorway they're going to be able to see the crater from space.
