You'd think so, but no. You beat the butter (and a bit of vegetable shortening - just like commercial buttercream) until it's light and fluffy, then add cold (like put the can in the fridge for at least 2 hours) condensed milk. Whip that too! There are a ton of tutorials on youtube.

Honestly? I think the American palate is more like a kids, they like things super sweet. I wasn't terribly off put by it, but the men in my family hated it. They wanted the sugar laden stuff. Too sweet by half!