3-5 times at least 

 😆 

 Depends on the situation.  In general, yes. 

 yes 

 I thought they only don’t say bye in the movies (for some reason) 

 I've noticed it lately on shows

That's why I asked 

Thought I was a weirdo 

 Bb buuuyyyyiiiiieeeeeeeeeee 

 I say ‘buy’ 

 Depends on the casualness/frequency of the calls. Typically I do not do so if it is someone I'm regularly on/off the phone with throughout the day. I'll say some form of "bye" if I think it's the last time I'll speak with that person that day. Someone I don't speak to on the phone regularly gets a "bye" every time. 

 Off course. Do you just walk away when done talking in real life?