A Frosty is what you get when you take ice cream, and pretend it's a drink. The Frosty was made to allow Wendy's to compete with the Big Mac of McDonald's and... whatever crap Burger King makes. Since the Frosty is not a burger, it is different than the other restaurants. Difference should be squashed out of every living soul, so consuming a Frosty is frowned upon in modern society.
The Frosty was first invented by Wendy shortly after opening Wendy's. Realizing her business sucked, she decided she needed a cheap gimmick to lure in a bunch of idiots. She took some ice cream, and filled a cup with it. She called it the Frosty, and sold it for $50. Other variations were developed over time, most notably the Frosty of the Gods.
The Frosty was further developed when Wendy realized how stupid she looked selling ice cream in a cup. She decided to add a little more butter than before, causing it to become more fattening. This caused it to be a hit in UnAmerica, where they eat anything if it makes you fat.
Multiple lawsuits were filed against Wendy at the same time on April Fool's Day. Biased Ratings, Facebook, and Nintendo thought it would be funny to "prank" Wendy's by filing three lawsuits at the same time. But then Biased Ratings wimped out and only two lawsuits were filed. It was supposed to be a prank, but some idiot accidentally got real paperwork filled out, and the two companies pressed the lawsuits so they wouldn't look like total idiots. The idiots also sued the Frosties themselves instead of Wendy.
Nintendo's entire lawsuit over Wendy's Frosty was over a Photoshopped picture. They took a picture of a Wendy's employee, and Photoshopped it so it looked like he was drinking out of the Frosty machine. It was obviously fake, but Nintendo somehow won the lawsuit. The lawsuit cost Nintendo over a billion UnDollars, and it was all for nothing. Wendy's had to pay Nintendo $5 for the trouble, and fire the innocent employee that was Photoshopped in.
Facebook's lawsuit claimed Mark Zuckerberg had thrown a "Frosty Party" for all of the Facebook employees, and they died from the Death Juice used for the chocolate. This party never took place, but the Frosties lost this 'suit as well. Wendy's solved this by making a second flavor... vanilla.
Some time later King Frost also sued them for not having 9001 grams of sugar like they promised, only having 9000 grams. He won and now Wendy's is forever in debt.