My dad was banned from a local Yu-Gi-Oh competition

My dad invited me to see a Yu-Gi-Oh competition he was gonna participate. No idea why since I don't know anything about the game, I guess he just wanted to share that moment to someone.

His deck of cards is very old, everything is original and he's been collecting since forever. The competition went well (way more cheers and screams than I expected for a card game lol). He get to the Semifinal and then he did something I understand immediately what was it. Like I said, I don't know anything about this game, but being raised by someone who is a fan I hear things, and I knew immediately what was gonna happen when he pulled an Exodia.

The whole room was quiet, everyone looked shocked. They had to pause the competition to see his cards because they only allowed original cards, and they were legit. He won. But then we had to leave, he told me it was like this with the local competition, they "allow" this because they don't think anyone in town has the original cards, but in reality they think this will make the competition boring, so it's ""allowed"" but not really.

They offered him a huge part of the prize to leave (unless he wanted to play the final without the exodia cards), he took the prize and was told he probably wouldn't be able to participate in the next tournament.

"I just wanted to show off" he said to me.

Apparently this has happened before with him, it's not a competition general rule, just a petty rule from SOME local tournaments.