They paid 15 million per year for RL for a long time.
Infact, it was less than that.
From Wikipedia:
Broadcasting Rights
"In 1998 Packer's Nine Network secured the free-to-air broadcasting rights for the NRL until 2007 for $13,000,000 a year. In 2001 C7 unsuccessfully attempted to buy the pay television NRL rights until 2006 for $72,000,000 per annum. After News resigned these rights, and acquired the AFL broadcast rights, C7 was shut down in March 2002 , leaving Fox Sports as the only Australian pay television sports network. As a result of the failure of C7, its owners commenced legal proceedings against parties, including Fox Sports, Foxtel and the NRL Partnership, for damages of $1 billion. This matter is still before the courts.
The free to air rights were renewed in 2005 until 2012 for an amount of $40,000,000 a year."
So, from 1998 to 2006 (9 years, inclusive), Ch9 was only paying $13 million/year (which was only a $1.6 million/year increase on the previous FTA rights, which had been $11.4 million/year dating back to 1994). I don't know if you think that's a lot or not, but it doesn't sound like a lot at all. Considering, that from 2007-2011 (5 years, inclusive), they've been made to pay $40 million/year, which is more than triple the amount (per year) they were paying the previous 9 years, even when ratings and crowd attendances were starting to dramatically increase again post-Super League.