The displayed scoring average resets when you level up, so his current average of 81 isn't what made him move up to tour pro.
I believe your average has to be 72 to move up to tour pro. But keep in mind that once you've played the minimum (20?) rounds, only your best 20 rounds are counted toward your average. So if your current set of 20 scores includes a 79, you can improve your average merely by shooting a 78, even though your average is below 78. The 78 would knock the 79 out of your set of 20.