I had the exact same observation but for another Apple app ecosystem: Game Center. I could not care less how I rank in the global rankings for an iPhone app. Do I care that some 10 kids or idiot savants have scored 100x higher than me? Not really. Maybe if I had actually joined a league or something I would like to know how I ranked globally but otherwise, that's not what you want to show people by default.
There is some pride in knowing that you are one of the 10 best people in the world at the iPhone version of carcassone but that pride gets to be enjoyed by exactly 10 people. Everyone else gets to see their relatively low scores compared to total strangers.
As someone who was once ranked 81st in the world on a game, it was a blast to see that my score was that high. Maybe it should only tell you past 1000, but it's a great little reward.
Over time the app became more popular and and I lost my rank, but it was still cool.
I wish Apple would fix the rampant cheating. While my rank was 81st, it was realistically ~60th because many of the top scores were simply cheaters who scored MAX_INT when that was at least 10,000x higher than the next closest score. That is the thing I find discouraging about looking at the scores, that every game is topped by cheaters.
Percentiles I think greatly help the appearance of rankings. Knowing you are in the top 95% vs. knowing you're a measly 2 standard deviations above the mean.
This creates opportunities for games themselves to showcase your rank relative to your social network. This is more meaningful and naturally reinforces engagement within the game, something the game developer cares more about than Apple.
Candy Crush handles this well, I think, via facebook integration. Amongst other things, it shows you the top three scorers on a level out of your facebook friends.
There is some pride in knowing that you are one of the 10 best people in the world at the iPhone version of carcassone but that pride gets to be enjoyed by exactly 10 people. Everyone else gets to see their relatively low scores compared to total strangers.