Man you brought back memories with Karate Champ, Star Wars and Paperboy.
A few years ago i built a raspberry pi with a friend of mine and we downloaded all of those games. I learned that i still suck at paperboy. But i also took the time to play through the entire mario series I think Mario 3 was my favourite. When i was a kid i used to pretend that i was in a game competition like in the movie The Wizard and that my score was my cash prize.
They definitely didn't design those games to be easy. They wanted to vacuum up our quarters!
And they often succeeded!