Netflix uses Docker in production. While they don't use it for everything yet, they are transitioning to it. Netflix accounts for 37% of internet traffic or more in North America.

http://www.slideshare.net/aspyker/netflix-and-containers-tit...

Maybe you had trouble, but I think that those that aren't using containers need to be aware that many are using them successfully. Use of containers vs. VMs/dedicated servers can also result in reduced energy usage and can be less expensive.

I think people get hung up on what containers aren't and where they fail, rather than where they exceed.