Inconsistent Policies

I got the add that Spar is selling 24 Baby Soft Toilet Paper @ R99.99 so I went to Westwood village branch after work only to find all stock Sold out. I asked the Cashier if I could get a rain check to which she advised they don't do that. I then asked to speak to the Manager which also advised that they don't do rainchecks apparently it's against their policy. I then asked when they're expecting more stock to which he answered maybe Friday.

I learned from my Colleagues today that they were given rainchecks for the Toilet Paper & Rice that was out of stock from the Branch they went to.

So please can you explain why is it that some stores offer their loyal customers rainchecks & other don't?