Because they're cute, a little pricey but still affordable, easily transportable for classes, a bit of a status symbol, and there's just nothing that sounds and feels like sewing on a vintage machine. It's a time machine, taking you back into yesteryear when things were simpler. I sew on a cabinet vintage machine a lot but every now and then I break out the FW. And sometimes it's a "just because" thing.
If you find one in good condition and a reasonable price, get it. You'll understand why once you played with it.