I mentioned in a previous question, when I moved out I accidentally took something that wasn't mine and returned it. Out of curiosity could this be considered theft? What if someone returns something before the owner even realizes it's gone? What if the owner never even realizes it's gone?
In Canada, theft requires "A person commits theft when, with intent to steal anything, he moves it or causes it to move or to be moved, or begins to cause it to become movable." (source) so does that mean if the defendant claimed it was an accident the plaintiff would have to prove otherwise?
In practice, do thefts smaller than a certain amount usually not go to court? For example if someone steals a coke can from a store, would they really get sued in court?
Also what if someone accidentally steals something consumable. For example you rent a house with a garage and filled up your car with a tank of gas but realized the landlord had an identical one to your own. Would this be an offence, and could you actually be taken to court?