I think it depends on which point the paper was in its distribution. The fact that is handed out "free" eventually does not mean that the owner does not have rights to the stock in the vans, warehouses etc. It's a bit like if I decide to hand out free Snickers for a promotion that does not give you the right to make off with my whole stock from the warehouse.
If on the other hand the papers were taken when they were just left out for people to pick up then it could be an interesting legal case.
Biting the hand that feeds IT
