Legally, this isn't even remotely true.
If you deprive someone of their legal possessions without permission, even with intent to return it later, you are guilty of theft.
There is no loophole that allows you to temporarily steal things as long as you intend to return them.
Intent only comes into play if the person had no intention of depriving the other person. An example would be if you accidentally pick up someone else's jacket because you thought it was yours.