$licObj->LicenseData(); doesn't call the same sub. It is another example of unfortunate naming in the code. There is an element of truth in:

There are only two hard things in Computer Science: cache invalidation and naming things. -- Phil Karlton

Naming things well is hard. However the big item here is that you aren't up to speed with what OO is about. The key is that $licObj is an object and methods (LicenceData() in this case) do things with the object. Maybe Not quite an OO tutorial will help make it a little clearer. A huge amount has been written about OO, but until the "Ah ha" moment comes it doesn't make much sense and even then it's likely not obvious where the benefit is. Used well it does make sense and there is a benefit.