I was watching my friend play Pokemon on an Emulator and he was playing for the first time. Since I was at his house the whole day, I watched him play through the entire game and I noticed one thing: All the events that happened in the anime happened in his game. Strange eh? Is there any explanation to this?
I know why.
Your friend was playing the ROM Ash Gray, which is a game where you follow in the footsteps of Ash Ketchum himself.
Source: I played the game before. Also, you can look at this.