Accused of theft yet innocent

Who on earth gives menlyn woolworths clothing the human right to accuse someone of theft without any proof😡😡😡😡😡😡😡😡 my brother inlaw purchased a suit at a nother mall. And wanted to exchange at .enlyn branch but since he cant find the slip hes accused of theft😡😡😡😡 who gives you the right. Instead look on the cameras before acusing😡😡😡😡😡😡😡 i feel like pressing charges