Can the game with no mods/cc cause LEs?

Yes, very possible. Just one that happens right off the top of my head, if you have a sim quit the spotlight, LE's from the game will happen (unless that has been fixed, I know it was a thing). Just with no mod, you won't be notified. You can delete any LE files in your documents/EA folder and - if you have no mods/cc - see any new ones that pop up from EA.