One of the reasons that Willy Wonka and the Chocolate Factory is such a great film is that even after you've seen it, you can't be sure you have a clear picture of exactly what the eccentric candy maker was really up to. While the man appears to be a kindly old business man, he's actually fairly crazy, and a new fan theory supposes that his plot was even deeper than we thought. According to the theory, Willy Wonka was pulling strings to make sure a kid like Charlie Bucket ended up with a Golden Ticket.
The theory comes from the home of all great fan theories, Reddit, specifically from a user that goes by paulvs88. The theory starts with the idea that the news report that claimed that the last ticket had been found in South America was intentionally falsified by Wonka. It is true that the picture we see of the man who supposedly found the ticket is actually a picture of Martin Bormann, the former personal secretary of Adolf Hitler (a joke that most people missed). The idea, apparently, was that the last ticket should be found organically, by somebody who just wanted to enjoy a chocolate bar, not by somebody who only wanted to win a contest.
Part two of the theory argues that the candy store owner where Charlie buys the chocolate bar is actually an undercover employee of Willy Wonka, similar to the guy who claimed to be Slugworth. After the fake ticket story goes out, he's instructed to give the bar with the ticket to the right kid, probably somebody poor, but who has a good heart. At first, when Charlie goes to buy candy with his found money, he just wants the biggest bar he can get. The candy store owner gives him a random Wonka bar. However, when Charlie turns back because he wants to spend what little money he has left on his grandfather, the owner decides this is the kid and hands him the bar behind the counter with the ticket inside it.
You can watch the entire exchange in the clip below.
In this theory, the idea is that Wonka would have wanted a local kid to win the contest because it would have simply been easier for a local kid to move his entire family into the factory. Also, with the contest ending the very next day, the kid would have had to have been local in order to make it to the factory in time for the tour.
Certainly, while the sequence of events doesn't discount this theory, it doesn't implicitly support it either. However, it has to be pointed out that Willy Wonka in this movie is an absolute lunatic who can't be trusted in any way. This theory is exactly the sort of thing that he could very well have done. We know he sent out a fake Slugworth as a test of all the kids and at the end of the film, he berates Charlie to see how the kid will respond. Why wouldn't he have also stacked the deck?