Marshalls review: returns with gift receipts

I tried to return an item paid for in cash, and was told by both the associate and manager that items returned with gift receipts may only be returned in exchange for store credit. My wife and I are regular shoppers at both TJ Maxx and Marshalls, and I find this practice to be unnecessary and unethical. It isn't the store's money, and we are unsure whether we will continue our shopping with this company and it's affiliates in light of this recent development.