Opal Approved Retailers Commission?

Further inquiries have lead to Opal approved Retailers who can top up Opal Cards, will only be paid 2 percent commission for every top u by customers.

Yet holding the cash and ensuring it it banked by the retailer is the risk the retailer makes and is it worth the commission? The main reason why Opal Ticket Top Ups cannot occur at Train Stations is because they are owned by 'Government' and Opal is a 'Private' Company. My understanding is that Private Companies doesn't want Government employees to collect money for them. How's that?