It's the result of a combination crappy customer support and idiot players. Jagex gets so many reports from wanna-be mods and 10 year olds for every little thing that they are forced to automate half of the reports they receive.
Would you want to sit at a computer and go through reports such as: "This guy called me a noob! Offensive language!" or "This guy mines faster than me... reported!" or people reporting each other just because they had a little arguement (in which they both cuss each other out, but report anyway)? I know I wouldn't.

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