Unlimited Storage and Traffic is a marketing concept hosting providers use. The fastest growing hosts all use this concept.
Unlimited Storage and Traffic does not mean unlimited CPU and memory usage. If a site started to use anything close to "unlimited storage" they'd obviously be using more than 10% of server resources which many of the large hosts have as a cpu and memory limit.
Sites will never use unlimited space cause the cpu and memory usage would limit that.
It's like selling a car that can go 200mph but you can't go that fast since the law restricts it. There are always other factors that can limit usage.
The unlimited hosts do not limit storage and traffic, but they do limit cpu and memory usage. They also limit the types of sites you can host like you can't use it for remote backups or host video sites.
"Unlimited" doesn't mean "no restrictions"
I understand everyone's point here, but unlimited storage and traffic is not going anywhere anytime soon. I too used to let it upset me but I see both sides of the issue now. Most of the top 20 hosting companies are unlimited now. If it was such a lie don't you think they would have been brought up on fraud charges by now?
BlueHost, HostGator, the list goes on an on of unlimited hosts... and most are the fastest growing hosts in the industry. Can that be so wrong?