No they can't. Unless they adjust the price and change the labeling on the box, they can't just remove content.
Now, will the Mexican authorities, who have to deal with drug cartels shooting people in the streets, care? Probably not.
Adjust the price? No, they could sell the disc without any boxes for 120$ if they wanted to.
They CAN just remove content, because you will notice it.
If you pre-order it, you ask about it to prevent getting scammed. If they lie, THEN its illegal.
If you buy it, either check the (already opened) box. Either they used some duct tape to tape it back together or just have it open. Either way, your fault for buying it.