Preferential treatment given to 2016 BlackFriday contract customers

I just learned that MTN retention department offers different contract bundles to customers. Customer who joined MTN in 2016 on Black-Friday are given promotional contract bundles of 100GB and 500 minutes for only R470, while other existing contract customers are offered meagre contract bundles of 40GB for similar price. It seems that MTN is taking likely existing customers who had been loyal customers for over 8 years. This is the same mistake ABSA bank lost customers by offering monthly account bundles to new customers vs old existing customers. Do not try and say it was a 2018 Black-Friday special as i have colleagues who have only been with MTN for about 3 years and upgraded weeks before this Black-Friday and on Monday (27/11/2018) past this weekend. This is totally unacceptable and exploitation of existing customers and preferential treatment given to certain contract customers. Why is different promotional bundles offered to MTN customers? This offer was not available at MTN stores on Black-Friday this 2018?