as in higher premium price received for the put you sold?
And a lower price for the call you buy. Normally the combo vs stock (a conversion or reversal) is simply a function of cost of carry and dividends. In a hard to borrow stock you can buy the combo at a discount to the normal rate. Consider someone who wants to short the stock. They can accomplish the same buy buying the put and selling the call of the same strike. Now they don't have to be bought in or worry about paying the high short rate, but it will cost them extra to put on this position. If you sell him this position, you will get this extra benefit. If you simply buy the stock, you are giving the extra money to the clearing firm instead who gets to make money loaning your stock out.