The book is a thinly-veiled parable for the Holocaust.
A mysterious building, with smoke coming out of several large chimneys, that nobody ever goes into and nobody ever goes out of.
The manic owner invites several people in and physically punishes them because of their undesirable physical traits. He is left with the heir to his kingdom - the blue eyed blonde white boy.
Another reason why it should be made to fade away.
Sorry but that's a stretch and a half. It's a factory in the north of England - they all smoke. People don't go in because it was closed after industrial sabotage and I'm fairly sure millions of people went *in* to concentration camps. They don't have undesirable physical traits (apart from Gloop, if you're fatist), they have horrible personalities and break the rules - and none of them get gassed and burnt, just amusingly punished and improved!! And I'm nearly 100% positive Charlie is never described physically, only on his virtues of being a nice kid. The first film actor is blonde and blue eyed but that's not based on any description Dahl gives, probably deliberately as his agent made him make the character
not black like he wanted originally. I'm pretty sure he's not actually described in terms of hair or eye colour at all in the book, just that he's a skinny little shrimp.
I mean, I know Dahl had some disgusting anti-semitic views but that doesn't mean Willy Wonka was frickin' Hitler!!!