Your first "how disappointing" was just over 6 hours after your original post. The majority of people that visit here likely have jobs they are at during that time. It's still been less than 24 hours since your original post.
As your question is device-specific (LG modifies the OS before they release the update), did you look through or ask in the HTC One M7 forum here?
On my Samsung tablet running KitKat (so it's Touchwiz and not Lollipop) adding additional users is done in General, Users in the settings app. This is to give you a general idea, it's also ENTIRELY possible LG stripped that from their version.