Seperate power supplies?

For some reason, I see a lot of tutorials powering the Pi from a seperate power supply. Is there any specific reason for this, instead of just using the 5V high amp PSU that is used to power the LED strip?

Ok, thank you.

..fix what?

I simply wire the 5V/GND on the GPIO to the power supply.
If I wanted to keep the fuse in play, I'd solder a micro USB cable to the 5V of the power supply.

I can once I am done wiring it up. But there's really nothing special to it.. 5V to Pin 4, GND to Pin 6.

Well, my ambilight is set up (minus final calibration) and works fine.
Power distribution is done via a power splitter board (actually intended for a drone originally), connected via an XT30 plug (can handle 30 amps).
All devices and the strip are powered from that board.
The PSU had to go down on the sideboard since the gap between TV and wall is too small. I'm using an original Raspberry Pi Zero (without wlan), hence the wlan stick on the USB hub.
Certainly not the prettiest wiring job, but it does the trick with what little space I have behind the TV.

i.e.
https://www.aliexpress.com/ite…ticopter/32668766530.html