There is a limit. However, all of this growth is partly due to previously unexploited advertising/marketing demand. Older mediums like newspapers/magazines, TV,

There is a limit. However, all of this growth is partly due to previously unexploited advertising/marketing demand. Older mediums like newspapers/magazines, TV, and radio only served to a small niche of potential advertising buyers. Facebook, Google, etc. make it easy and cheap for anyone to advertise pretty much anything.