That's a good point but it's also important to note that a Snickers bar has much less nutritional value than the cheeseburger shown in the original image. So if you're training for a marathon or something, you can totally get away with a cheeseburger every night, but not the equivalent amount of snickers (you will feel like absolute shite)

i think that's technically true but reductive, you will continue to burn calories at a higher rate for quite a while after any reasonably strenous exercise and as you get stronger it becomes easier to burn more calories, thus letting you increase your daily calorie budget.

I'm not saying that five minutes of cardio will suddenly let you eat 5 cakes, but have you seen the diets that weightlifters keep? with a lot of muscle and frequent heavy exercise you can burn such an amount of calories every day that eating 3 pizzas is a good starter course.

Also we aren't talking about a bad diet, just eating a bit too much. Of course exercise isn't going to fix you eating snickers instead of vegetables but it will absolutely fix eating one too many burgers.