There's a really wide gulf between building something in a lab and scaling production to some industrially useful level. The money spent on the LHC wasn't just

There's a really wide gulf between building something in a lab and scaling production to some industrially useful level. The money spent on the LHC wasn't just lot on fire in a giant pit. It went to contractors that took lab scale prototypes or just paper designs and built them at scale. Building a one inch super conductor in a lab might be straightforward but cost a million dollars. That lab process doesn't scale to building seventeen miles of superconductor. The LHC needed 4722 miles of superconducting cable. Simply manufacturing that much cable led to advances in superconductor manufacturing and design. Even then the LHC's particular superconductors only work if you've got the operating budget to use liquid helium to cool them. The money spent went into research to develop the components necessary for the design and then into the production of those components. The LHC wasn't some item picked out of a catalog. Many of its components only existed on paper when it was designed. No one is just going to pump development dollars into some paper design and hope someone somewhere finds a use for it. The LHC's superconductors advanced the state of superconductors in general but no one was going to do that work without an end goal and a budget. Military development ends up with a similar model. Requirements for a desired capability are given to a contractor and they need to figure out how to build it. Sometimes that development is easy and other times it's difficult and expensive. Contractors definitely make a profit and pad co tracts but that money does pay people to do things. The requirements and funding create a market for the development for technologies that meet those requirements.