I think it's worth pointing out that ZeniMax has been pursuing this since 2012, long before the Facebook acquisition. At least according to this article on ArsTechnica:
it might be true that they were pursuing it earlier, however, according to the WSJ article that is the source for all this, the lawyers didn't get involved until after the Facebook announcement.
The letters from ZeniMax's lawyers came after Facebook struck its deal to acquire Oculus, part of the company's efforts to leap from a social-media platform to a major player in the race with Google Inc., Apple Inc. and Amazon.com Inc. to be at the forefront of Internet use.
A bit off-topic, but my favorite example of incentives gone awry in sport occurred during the 1994 Caribbean Cup (football), which ultimately resulted in one team defending both goals while the other team tried to score in either. In this case, the rule that caused the chaos was recognized to be poorly thought out and replaced in later tournaments.
Not only it's on-topic, it's even more amusing. At some point one of the teams was trying to score +1, but as the time passed it became safer to score -1 for a chance of +2 later; after deciding on scoring -1, the situation sort of reversed and the other team tried to score either +1 or -1.
[1] https://github.com/bitwarden/core/blob/master/LICENSE.txt