Paying for something in one location but not another like BBQ sauce

I think I need to report this to the BBB. I went for lunch yesterday at the location at 3477 Brunswick Pike Princeton, NJ store # 00008022, and they charge 50 cents for a small thing of bbq sauce, my daughter then decided she wanted Wendy’s for dinner and I didn’t want to disappoint her so I went along with her at the location at 760 Route 130 South Hamilton, NJ 08691 store number 00008686, and I got BBQ sauce there as well and WAS NOT CHARGED. I don’t know one store can charge and another not, when you are a chain restaurant I think this needs to resolved and reported.