Here’s what consumers have asked with answers from Cu.cc staff and previous consumers.
No they are not. Cu.cc is a free domain service. If a legit company is really operating buying a paid domain is a way to go, and if you check their site their are no links on Facebook, Twitter and other social media accounts. I suggest you report the scam company to http://www.registry.cu.cc/abuse.php for them to take action and delete the domain.