I don’t agree with the popular headcanon in the WIR fandom that King Candy often threw fancy parties in the castle (parties that Vanellope was never invited to, of course).
I don’t think he let anyone in the castle if he could help it. Only the guards, Sour Bill, Duncan and Wynchel, and prisoners. He wouldn’t risk having large, uncontrollable crowds in the castle, for events during which he couldn’t keep track of every person’s whereabouts. Someone could easily wander off and find the code room or some other clue that he wasn’t supposed to be in there. Even Ralph noticed right away that there was something off about the living arrangements when he made that salmon comment.
It’s more likely that he saved the castle as his retreating place and closed it off from the public. There he could let his guard down a bit (just a little bit) and enjoy his stolen luxuries without having to put on an act for the people. No parties, no balls, no gatherings in the throne room. Just him and minimal staff.
There’s a song by Baz Luhrmann called Sunscreen. He says, “worrying about the future is as effective as trying to solve an algebra equation by chewing bubble gum; the real troubles in your life will always be things that never crossed your worried mind.”
“The next morning as I watched them pack, I saw the men in a different light. Not criminals, but rebels. I wished I could tell them that they were on the losing side of history. That it was all a pipe-dream. The Stuarts would never unseat the protestant King George the Second. But how could I tell them that? These proud, passionate men who lived and breathed for a flag of blue and white…”