Why does the standard Arduino IDE not include the CH341G USB Drivers?
This is simply because the CH340G is not supported officially. The Arduino IDE is meant primarily for genuine Arduinos.

What you could do is repackage the Arduino zip file with the required library and create a basic script file to install the drivers with just a couple of clicks.

Or you could shift to another board that uses the ATMEGA32u4 as this might not require anything special. Have a look here. I don't have tested this board so you will need to check the quality and whether it works with your projects.