All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
The questioner should repent from what he did by fulfilling the conditions of a repentance mentioned in Fatwa 87903. Purchasing goods less than its actual price without the permission of the owner is deception, cheating and stealing the money which is not paid.
Among the conditions of repentance is giving back the rights of the people. Therefore, you have to pay the difference of the price of the suits to the owner of the shop. If you fear that he may harm you, then it is not compulsory to inform him of the reality. It is enough to return the money by any means such as putting it in the cash register or any other safe way; what is important is that the money should reach its real owner. So, you are not relieved from your responsibility by burning the suits, as this is destroying the money. You are not relieved even if you give the money to a mosque or poor people as long as you know the real owner and you are able to pay back his right. You become free only be paying back the money to its real owner.
Allaah Knows best.