Let me translate this article for you.
After wasting five decades, scientists announced that they have proved something that Einstein told them existed 100 years ago. A group of people from at least two countries said they spent over a billion dollars to build a machine to test Einstein’s theory. When asked for comment, one of the scientists said, “This is amazing! We spent a ton of time and money listening for these waves, and now that we’ve heard them, we can listen some more! These waves can teach us so much about the universe!” When asked what exactly, he was predictably vague. “All sorts of stuff about things and science!”
The article then gave credence to the discovery by referencing the fact that Einstein’s theory was referenced in two fictional movie series, which are not based on reality.
When asked what practical use humans could have for this discovery, the scientists said, “Well, nothing really, but it’s great that we get to keep spending money looking at stuff!”
Words of Truth 
Ha. As Emily said, they didn’t have any use for electricity when Ethyl first discovered it ether… except at parties maybe… hit some poor unsuspecting partier with a jolt and make em yell. WHAAAA! (Cue laughter from other party goers.)
Ethyl? Is that you Ethyl?
And since the ancient Greeks knew about electricity (at least the static form). I think it would be hard to pinpoint exactly when it was discovered. But you are correct that no, “they had no use for it when it was first discovered”. I’m not saying this gravity wave thing is of NO value, I’m just saying it’s not really a big deal right NOW.
It would be like if someone invented a device capable of moving people backwards in time to 2145. Since we have no way to go FORWARD past 2145 other than the usual “wait 1 second per second”, the invention would be useless until 2146.