I have floppy drive wherever there's a shaft in the case for her and connector on the motherboard (last I had on LGA 1155 ASRock Z68 Extreme3 Gen3).
And the reasons?
1) I like the sound of the PC boot when the drive verifies the presence of the floppy disk (yes, pure nostalgia)
2) DOS boot disk for W98 and other small DOS utilities (RAMBIOS, flashing utility, etc.) I find useful just on floppy disks, as many BIOSes can boot from FDD, but no from CD/DVD drives
3) saved my board several times after the flash of modified BIOS, when the board booted, but without the image on the display. All you had to do was boot from the boot DOS floppy disk, wait until the drive's LED goes off and swap the floppy disk for another with the flash program and backed up by the original BIOS. After a blind flash, the boards were saved again.
Yes, there would have been other ways, but this way the floppy drive made it simple and quick.
For me, a floppy drive, like a CRT monitor, is simply a piece of hardware that I must n't miss with a retro PC.