This is kinda like the rules that Visa has on it's merchants. You can't charge more for using the charge card, but you can give a discount for paying cash.
You can't charge a man more for using the range, but you can give discounts. The range charges everybody to use the range on Monday, but they give the ladies a 100 percent discount. Just like the way that Lowes and Home Depot give 10 percent discount to Veterans.