I don't know, I'd think the type of owners should be somewhat similar since both cars are also very similar and direct competition with each other. Maybe it's because there are a lot more WRX available in Malaysia hence easier to find good condition ones. If you go thru car advertising, you can see so many more WRX than Evos of the same generation. The prices are also much cheaper compared to Evos.
Yes, the WRXs are a bit less hardcore than Evos, and interiors seems nicer/more luxurious than the spartan Evos. That's why maybe also people buys the WRX more hence there are more second hand available too in the market. Or maybe those having Evos are more hardcore drivers who abuse the car more also.