From a security standpoint, it is easier to secure their intellectual property and their new ideas in a campus setting than one where all their people are spread out.

Fifty-acre parcels are generally not that available in Silicon Valley. You can't buy 50 acres, you have to piece it together. So if you're Apple and you're going to go through the trouble of putting it together, you might as well pick an area you want to stay in, as opposed to one further away where you might save money but it will be just as difficult to assemble.

In a campus setting, it's more of a secluded feel, as opposed to a high-rise. Plus, there's room for other facilities and amenities, such as more parking or a soccer field. When groups are working together, they don't have to get on a bus and drive to another building, they can just walk.