People dip them in! lol no idea when the craze began but it's soooo good!!
It's a very highly debated practice lol me and my friends have gotten in screaming matches over it. Some thing the salty + sweet combo is amazing, others think it's an abomination
So, I tried my fries sprinkled with malt vinegar tonight. It smelled like Chloe's feet when she wears shoes without socks and tasted exactly like hot sauce without the best part... The hot. It wasn't disgusting but it really just made me wish I had used hot sauce instead. Probably won't ever do it again. Definitely my least favorite fry topping. It just totally covers up the taste of the fry.
My mom does the french fries in the frosty/milkshake thing. I'm not a big salt eater. I won't ever go out of my way for fries but when I do good old ketchup does the trick for me.