It depends.
Mopar did it for certain options on some cars, such as clocks, convertible tops, and rear defrost grids. However the last involved a rewire of the alternator feed direct to that stud.
It depends on what the loads are, and whether these items should have the key on run or accessory to operate.
It depends on how its done. The wires need to be routed so they don't get twisted the wrong way or chafe on sharp metal, etc. There will need to be appropriate fuse or circuit breaker since you're tapping off the main. Things like that.
