Why does america and france seems to never go another way ?

Hi, bit of a random thought. I have noticed that in all my non-historical games, the USA and france seems to never opt for something else than their basic democratic path, wich is kinda extremely boring in my opinion. I'd like to see more american civil war or french napoleon (wich btw litteraly NEVER spawn in even though it's the best path by far).

Any Idea as to why these two seems so "stable" in particular ? Or is it juste me that had this experience ?