I don't think there's anything inherently bad about it. One thing I've heard as a reason to avoid late-night eating is that willpower tends to decrease as the day goes on. Therefore late at night, you might be more likely to give in and eat those super-high-calorie foods, like a bowl of ice-cream or greasy takeout. It's not that eating a bowl of kale at midnight is worse than eating one at lunch time.
