I think a lot of this probably has to do with the fact that the ducting to the rear seats runs under the cupholders and armrest. You might find it is heated in the winter when the heater is on.

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2017 Nissan GTR Red/black - Tune/midpipe
2013 BMW X5 50i M-sport Alpine white/black - Dinan stage 1
2016 Jaguar F-Type R Gray/red