But imagine this. Each time one of these services is charges to another business segment at commercial rates there is a little thing called GST, sales tax and other taxes. If commercial rates are charged based on business segmentation for stand alone group businesses, the tax bill would be astronomical.
Nope, any GST they pay to other group companies is credited to them from GST the collect from customers.
The consumer always pays the GST, and companies claim a credit on the GST they pay.
If this were not the case, there would be a 10% tax from factory to consumer. Ultimately business passes the tax on and gets credits for everything they pay.