Sometimes when you have a sensitive relationship, it can be helpful to support the thing that makes the other company uncomfortable without openly advertising it.
what relationship? Valve is pretty much PC only other than some ports of old source engine games. Nintendo is first party console and handheld with couple of iOS/android apps. their isn't really any relationship to be sensitive.
No one is abusing the legal system. They're using the legal system. The way to fix it is not to try to stop people using the system 'wrong', but to update the system so it's appropriate for modern tech.
While that's strictly true, morality is not the same as the legal system. Using the legal system in ways that other see as immoral does not and should not make friends.