A 9 year sentence is rarely 9 years...
If your figure of an average prison stay of 5 years for rape is accurate, it is way too low for such a horrible crime. It would be interesting to see what those rapists were sentenced to as compared to what they served. Odds are, they were sentenced to at least 10 years but with things like "time off for good behavior", they were released early. Likewise, even if these fraudulent spammers are sentenced to 9 years, they'll probably serve no more than 2-3 years.