Unlocked cell phones allow us the consumer to avoid the ridiculous fees associated with buying a new phone from a carrier (more ridiculous if you don't sign a 3 year plan), and having to sign a stupidly long contract...
Why can't we do what we want to, to the things we buy?? (Maybe I am wrong [and please correct me if i am], but I'm pretty sure no copyright is being broken when unlocking a phone)