I already asked a related question on stackoverflow. Please see the reference.
What's the benefit especially for the Stack Exchange network to link the title to the same permanent page?
There can be very many links that link to the same page. For example, each answer and comment has it's own unique url. So if you are under that url, but just want to copy/paste the question url, you can just click on that link to get the correct link you want to copy paste from the address bar.
For example, this is the link to @Doorknob's comment on your question.
and this is the link to my answer on your question
So if I wanted to share the link of your question in a chat room or another post on the SE network, but didn't want the page to go to @Doorknob's comment or my answer first, but just load the page normally starting with the question at the top, I would just use this url :
However, if I wanted to link to your question/this thread somewhere else on the internet, like Reddit, I would use this url
https://meta.stackexchange.com/q/242210/244519 ^^^ my UserId, so your's would include yours when you click on share in your question
Because you can get badges, like the Announcer for bringing others to the site.