lonfield:
No technical reason. I just felt that it wouldn't add the example per se. It's also trivial to add a setup() and a loop() to the main() in the example in the same way as it is done in Arduino's main.cpp.
Just as with your product description I think you need to consider carefully how you present your examples to the market you are aiming at.
Stick with the Arduino programming style. Don't make it hard for people.
...R