Retained Accessory Power question

[Someotherguy]

I just finished replacing my front speakers with an amp and it's getting power from Pin 8 in the fuse panel near the brake pedal.

 

Can someone tell me what happens to the *stock* system when you turn off the truck, take out the key and open *only* the passenger door?

 

Currently when I take out the key, the front speakers stay on, but if I open then passenger door only; the front speakers stop playing and only the rear have audio coming from them. When I open the driver door everything turns off as it should. I'm not sure that Pin 8 is a true Retained Accessory Power pin, or whether I'm just crazy and that's how the stock system behaved as well.