Yep, /mnt is another place Linux uses for folders like that. Like I said, they really can be anywhere, but /shares and /mnt were the two most likely locations.
Some servers, such as Plex, wants different locations for movies and TV shows. Others, such as Serviio, aren't as fussy, and can mix movies, TV shows, music, and pictures with a standard file structure. But I find it's best to segregate them, for file tracking if nothing else.
I hope that's all you need, and you're good to go now. 😄
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