The premise is something only a marketer would come up with: all the popular brands and mascots - such as Charlie the Tuna, Mrs. Buttersworth, Twinkie the Kid, and more work together to fight off an evil "Brand X" that threatens their existence. It's CGI animated, and will promote the already well-known brands while cementing the idea in kids' heads that these brands are "good guys" and anything outside of that is evil and to be avoided. What could possibly go wrong?
How about everything?
The animation is awful. Some of the character movements are very puppet-like, and special effects such as a spilled carton of milk look ridiculous, as the milk spill looks like it was painted onto the floor and grows in size. Sunshine, the main character's girlfriend, is perpetually smiling no matter her mood - it's as if the modeler who created her graphics accidentally created her mouth in a :D shape and forgot to make it flexible.
The characters make no sense. Okay, I understand that this is a world where food mascots all coexist, so naturally there will be a lot of variety, similar to Wreck-It Ralph's world of diverse video game characters. But while Wreck-It Ralph created original characters who believably could have come from games, Foodfight!'s original characters would never be used as a mascot for anything. Who in real life would use Dex Dogtective or Sunshine as a mascot? Sunshine is a human with cat whiskers and cat ears, who can never stop smiling, even when sad. Why would any food company use that freak as their mascot? Along with other characters like naked gerbils, if these are supposed to be mascots... I just can't see it happening.
The story is loaded with puns, and puns are the source of most of its humor. Sure there's some jokes involving weird logic, like when Dex is trapped inside a giant dryer and finds a way to escape by following a sock ("Socks always escape from the dryer! Follow that sock!"), but most of the humor involves food-related puns. And many of those puns are sexual double entendres, a very questionable thing to put in a movie that's aimed squarely at kids, that no adult could possibly enjoy.
And speaking of questionable, there's straight-up murder in the story, some onscreen. Not many kids' movies have the balls to actually kill characters, but I'm not proud of this one for doing so.