The cellular networks seem to think we are all just as stupid as the government seems to think we are.
It is abundantly clear on these screen shots taken today from the Vodacom, MTN, and Cell C websites that they are either price-fixing or colluding, or deliberately being anti-competitive in their pricing for ad-hoc mobile data bundles. It must be more than coincidence they all arrive at the same prices for the same data volumes, yet each has a very different network infrastructure, backbone and peering configuration from the other.
I hate it when big corporates assume they are more intelligent than the consumer.