C64 programs went both ways, generally bigger and more professional programs used the extra ,1 because it gave them a little more RAM I think. Typically you didn’t have to type RUN to start them either.
This shouldn’t really be all that impressive. This is exactly the sort of thing the C64 was good at. It’s also one of the few games where the single button on the joystick wouldn’t be an issue. 
The C64 always inhabited a world somewhere between a full on computer and a game console.
