Why is the VPN market growing?

Why is the VPN market growing so fast? It's adding about 10% to the cap every year. Is there really such a need for VPNs? I see them marketed everywhere, but does an average person really need it if they are on their home WiFI? The VPN companies have a lot of money to blow on advertising as well, so it's profitable. I'm just surprised by the large demand since I thought it would be a niche...

Why is the VPN market growing?

by Jeff via TBN