I've mentioned in other articles a widely applicable principle: refusing to help when you can do so without cost to yourself is the same as hurting. There is, of course, the apparent implication that freeloading is moral, and not only that, but that preventing freeloading is immoral. Or is there? Let me explain.
First, we need to talk a little about debt. Debt is owed to someone who has made a sacrifice to help you. You do not owe someone who helps you at no cost to themselves (such as a god with infinite power and supposedly complete benevolence). By the same token, it doesn't count as your repayment if you help the person back at no cost to you - only when you make a sacrifice for them. Another principle is that you can never owe repayment past the point where your sacrifice is equal to theirs, even if their sacrifice hasn't been fully made up yet.
But, the hardest case yet: the case of someone who puts effort into creating something - such as a video game - and then makes it available for purchase. Is it wrong to pirate it? Even though the sacrifice made to create the work is now a sunk cost? My answer is that they should pay what it's worth to them. If a game costs $10 and you'd rather spend that money than not play it, then you should pay. If it doesn't matter to you that much, you'll just go play a different game if you don't end up buying this one, then it's moral to "steal" it in a way that doesn't hurt the creator at all.
One last thing. Since the above answer leaves the decision to the player who is incentivized to steal things they'd be willing to pay for, throwing obstacles in the way of freeloaders actually is moral, despite that freeloading is too in some cases. Because if you let everyone freeload without any obstacles, many people who would (and therefore should) pay are going to do that instead. That means making freeloading difficult for everyone is acceptable, because it prevents theft.