Main reason was I was tired of all the electrical problems I had with mine since the day I bought my truck.
Second reason was because when I swapped to a carb, I was still running nitrous. It was considerably cheap to go the carb route than it was to upgrade the fuel injection.
Lastly I can tune it myself because it's easier for me to understand. I've had EFI live twice now and I can fumble my way around but I don't fully understand it. Call me a simpleton if you must, but it is what it is

Then since I made the switch to boost, it only made since to stick with the carb. I still like it. And, there are alot of cars that still go very fast with carburetors. Fuel injection is definitely the way of the future, but there is nothing wrong it a well tuned carb. I love mine