Actaea

I find such reflections strange. Why did primitive people invent tools? Wasn't it to make their work easier, to make it more efficient? Why have civilizations throughout history developed weapons? And what about everyday conveniences – aren't they born out of a real need for them?

Well, look. Let's say there's a cell – the simplest part of an organism. Studying it is useless, right? But the knowledge you gain from studying it will help you better understand the principles of how the organism functions. Very soon, you'll notice that cells infected with a certain virus differ from healthy ones, and this can help in creating a cure for the disease. Add genetic engineering to the mix, and so on.
You'll say – but animal behavior is useless and doesn't affect anything! Who knows. I think that the first people who stared into microscopes at some unknown nonsense were also seen by society as doing something useless. The picture of the world is a very complex thing and is formed from a great many different pieces of knowledge about the world around us. Therefore, rejecting any research because of its "uselessness" in the short term is short-sighted.

Added 1 minute ago

And the argument "they made a special camera to make it more convenient to observe" doesn't seem very strong.

And this camera turned out to be so great that now they put it on your iPhone so you can secretly film what the girls have under their skirts! Is that better?