Why should “we” care?
Speaking for myself, I care because I have empathy, as I feel most or all animals do inside. We’re all Earthlings. They are us. I am them. That is, I identify and sympathize with the whole living and unliving planet I was born on. I care about the dirt. I feel that people who do not understand that they care too, just are not aware that they too do really care, somewhere inside, or with some part of them that is not with their current thoughts at the moment.
Speaking from within what I project may be the mindset of someone who isn’t aware that they care, and who is thinking from some “practical” human-centric point of view, say the executive of a mega-corporation: I would care because I would understand that in order for me and my family and my mega-corporation to continue to exist and prosper, ultimately, and perhaps sooner than I know exactly how now, all my interests are dependent upon a healthy planet. Specifically, if the planet dies, we all die, horribly. Really bad result. Trumps everything. Moreover, the people who are very smart experts who devote their lives to fields like ecology, have been saying for decades now that we are in big big big big big big big big trouble, maybe not today, or not for a few years, but before the end of my lifetime, and possibly in the next 10–20 years. They are also saying that biodiversity and ecosystems are really very very very very important to continued life of Earth. So is climate. In fact, just about everything on the planet is interrelated, and the systems which keep Earth habitable by Earthlings (including humans and penguins) have been massively impacted by human population growth, agriculture and industrialization. Species in particular take a huge amount of time to evolve, and once extinct, are gone forever, and every species tends to help the whole Earth ecology survive and be healthy. The worse off other species are, the closer the whole thing, including I and my mega-corporation and its bottom line, are to misery, disaster and extinction.
So healthy, happy penguins are good and necessary long-term investment.
Not to mention that healthy happy penguins increase the chance of everyone surviving and living good lives.
And they are cute and interesting.