certain 5 1/4 fan cpntrollers and other accessories use that for its power its not just for floppy drive infact most peeps dont have a floppy i havent had a floppy drive in 5 years no need for one everything can be done by flash drive or CD.
I have a brand new Seasonic power supply that came with a couple of floppy power connectors. My brand new motherboard came with a couple of flat ribbon floppy disk cables. I have haven't used a floppy drive or other IDE device for years.
I guess there is someone somewhere that might still use the cable.
Floppy disk drives, cd-rom drives, firewire, reset switches on pc cases, and case speakers have all been replaced by new and improved components. It is just a matter of time before legacy components disappear completely.