If they already knew the intended results it wouldn't make sense to do it. Science of this kind is like "here's something we haven't tried yet", which itself is pretty difficult to even come up with.

Also, money spend on something like this doesn't just disappear. It goes around the suppliers doing it and returns to the state eventually. Of course someone will pocket some money but when talking billions it's more of an investment in the area than a cost or even an investment in the actual collider. A used collider isn't worth that amount of money , so where'd it go? It didn't disappear. Money goes round.

It creates a lot of jobs and when looking at the entire supply chain, it feeds a hell of a lot of people, even if the scientific result is "oh well it didn't do anything at all." That way, it might be cheaper than supplying social security/basic income for that amount of people.

At the end of the day, in the grand economic scale, we're all riding on the shoulders of whoever digs out the the resources from the Earth, so we need to make these kind of very important projects to make it appear as if everyone else is actually producing anything at all. The science is just a nice side effect.

Will this do?