Not too weird. That's just how high the score counter goes. You can keep playing after that, but the number stops going up. (source: I've gotten that score myself. (although I paused every hour or so when my arms fell asleep, so that disqualifies me from submission))

I don't know. Assuming that he scored the original record because he was an avid player, he probably spent a lot of time naturally honing his skills afterwards, and with no one else to beat it for a while, he didn't have any reason to defend it.

Some people play down to the level of their competition.