Look, I used to like parking up by myself in nice quiet spots. But unfortunately there are some thieving people out there. So I have to choose more secure and less quiet spots to ensure the load is secure. I also need my boss to buy strong padlocks. The thieves aren’t my fault but I need to take account of them.
If my cargo is nicked, that doesn’t mean I’m a thief. But if I’ve parked somewhere dark with open doors, am I being a good, competent driver? I say not.
Same with clandestine. Having them in the trailer doesn’t automatically mean you are guilty of people smuggling and are going to jail. But it does mean you will be investigated.
As Mazzer says, it is not a perfect world, nor a perfect system, but it is what we have.