Real ones. Not the Wii thing.
Now, keep in mind that, in middle school, I was in 4-H from 5th grade to 9th grade, decided to quite, and came back again as a Junior. And stayed in it as a senior. And then I got to college and joined collegiate 4-H and now I'm doing their webpage. Needless to say I spend a crapload of time at county fairs, and the Ohio state fair (which is apparently one of three reputable state fairs in the nation).
Anyway, a two observations.
Rigged games don't seem to be that common. A notable example is that with the Fool the Guesser thing, the guy'll write something that looks like Ja. or Ju. and can says it's January, June, or July if you tell him to guess your birth month. I've tested this. It's иot true at the fairs I've been to at least. However, some games -- which are, in a sense, more like weird little physics puzzles, like that bowling ball rolling thing -- don't necessary have rigorously checked specifications, so it's a matter of watching
Second: There are games where you're pretty much guaranteed to win. Balloon pop games, for instance, are commonly cited as being rigged by having dull darts that don't fly well and underfilled balloons. On the flip side, there are ones that have overfilled ballons, sharp darts that DO fly, and about two feet between you and the baloons. You seriously cannot lose something like this. Also, the prizes tend to be decent, and it's less about skill and more about how much you're willing to pay to get the prize you want.
These games tend to do less business. I really have no idea why as they're only marginally more expensive than the ones where you're a lot more likely to lose at. I guess it depends on whether you're after a souvenier or after winning. Although the machine gun games are fun to play just for the hell of it because jesus christ you get to shoot pellets at stuff really fast this is awesome and you can still feel like a winner even if you lose as long as you shoot out more than the other guy next to you did.
Third, Skyline Chili's jingle really sounds like the Dragon Quest composer dude wrote it. Seriously. I'm so fucking hungry.