They will certainly argue, and win, by saying that for legal mumbo jumbo reasons, you only have permission to play it in the exact ways they say you can, and if you already bought the game, but they say you can't play, then it's illegal to play.

Which is why coming at this from a legal perspective a farce. Most of the world is like this, actually. You can assume that if some action brings money to large corporations then it's legal and if it takes away their actual or potential revenue then it's illegal. Go with what you feel is morally correct.