Hermione didn't really see the harm in letting her son cross the village in the middle of the day. Hogsmeade was still a safe village in her mind. Ron might have changed over the years, but she didn't believe he'd ever harm her son. But, she knew better than to disregard Antonin's orders when it came too their son. He would be furious if they were disobeyed and if anything happened to Oliver because of her carelessness, Hermione didn't doubt that he would make her pay dearly.