legal philosophy – Is it a crime to buy something on behalf of someone else?

It is alleged that gangs are responsible for supplying boats to people in France, who then use the boats to cross the Channel between France and the UK and then enter the UK illegally.

If these gangs in France buy these boats on behalf of someone, are they breaking the law?

Is it the responsibility of the boat owners what they do with those boats, and not the gangs?

Are the French authorities powerless to prevent such activities because these alleged gangs do nothing illegal?

Would the French authorities only be able to arrest and prosecute these gangs if they have evidence that these gangs are doing something other than buying boats on behalf of a group, and that this is considered criminal?