People love their dogs and are willing to spend large amounts of money on them - how do you prevent people from selling them snake oil?
On top of that, we're talking about the first-ever drug approved solely for the purpose of life extension - yes it's in dogs, but it's a topic being heavily pursued in humans as well. While the approach taken here isn't directly relevant to people, one can imagine that developing this class of drugs in animals could lead to useful information on how to do so in humans, but only if there's actual evidence to prove their validitiy.