Possible explanation that wasn't explained well: In the book there are different types of places with different rules. Some are original Halliday worlds, and then there are add ons made by others. My guess is that zone was Halliday hard coded and they couldn't edit it very easily. In the book, when Wade creates a fake identity and manipulates IOI into indenturing him so he can hack them from the inside, he is just working a real world tech support job. He manages to have a bomb delivered in the Oasis to destroy the force field from within though.
As for IOI, they are just the world's biggest Internet Service Provider (and 2nd biggest company, as said in the movie), and hellbent on controlling every aspect of the Oasis because it's essentially running the economy.
I still think the movie was a lot of fun, but I wish we'd gotten more of the first act of the book. Jumping into the first challenge so quickly hurt the movie I think.
As for IOI, they are just the world's biggest Internet Service Provider (and 2nd biggest company, as said in the movie), and hellbent on controlling every aspect of the Oasis because it's essentially running the economy.
I still think the movie was a lot of fun, but I wish we'd gotten more of the first act of the book. Jumping into the first challenge so quickly hurt the movie I think.