Would like to know this myself....can only get a subscription on my android phone...but all progress I make on it doesn't cross over to my PC. Kinda shady sales tactics if you ask me.
Most likely they are using the Full Auto upgrade. You will see the big point jump when you have targets you can shoot multiple times.Another possibility is some courses have those moving blue targets at the end. They're worth 1800 a hit. If they get to that stage faster than you then they have a lot more time to rack up…