Lets say there are two groups. One group builds a generic media client - under the guise of better delivery of free educational videos (MIT lectures etc.)
The other group sets up "Movie Copyright Watch" and publishes an up-to-date list of movie torrents - under the guise of occasionally reporting this list back to MPAA and the like.
Now lets say team A decide to adopt the same configuration format as team B uses to publish the list.
Neither team has done anything wrong and the resulting application is capable of infringing copyright - and is essentially equivalent to what popcorn time has.
What is the difference? Tools are tools - it is crazy to ban knives because you can stab people with them.