When you are in Sweden you have the right to walk, cycle, ride, ski and camp on any land with the exception of private gardens, near a dwelling house or land under cultivation. We call it the Freedom to Roam.
Its just a simple matter of C-Y-A. NJ wont allow you to walk down that trail because if you fall or get hurt you can sue the state and you will win. I cant imagine its like that in Sweden or maybe any where else besides California.