Contrary to what you might think, you're not getting ripped off at the fast food joint just because the burger in the ads looks so much better than the real-life one. In fact, according to a YouTube video released by the McDonald's marketing team in Canada, they use the same ingredients. But one of the major differences is that the content is pushed to the front. This helps the ingredients look more visible and, yes, even makes the burger look bigger and better.
After the pictures are taken, there's also some photoshop magic that make the burgers look even more appealing. Watch the video below to see how the process works: