Salt + fat + sugars = tasty.
Or at least that's what your brain will tell you.
The evolutionary psychology take on obesity and fast food is fascinating. If you're not familiar with it, it essentially says that high fat, high sodium, and sweet foods are delicious to us because finding such foods would have been like winning the lottery in our hunter-gatherer past.
And fast food purveyors exploit this evolutionary hangover by cramming their foods full of the things we as a species love.
The field has a similar take on alcohol. Fermentation would have signaled extremely ripe, sugary fruit in the past. Lots of energy, less time finding/gathering sufficient calories to go about your daily tasks.