I know many many people over 30 who play.
Lots under 30 too... if you were to make a graph of it...
01-10: ===== 5%
10-20: ======================================== 40%
20-30: ========================= 25%
30-40: ================== 18%
40-50: ======== 8%
50-60: === 3%
60-70: = 1%
In that general ballpark... but really, how would we even know what the stats TRULY are? We wouldn't without the MS creators doing a server-wide poll on every single account. Even then there'd be a massive % error for the poll being incomplete still or dishonest replies. Blah blah blah... so we can only guess.
My guess is the bulk of players are ages 10-40 with a dramatic increase in numbers starting at age 10 and dramatic drop starting at age 40, followed by another dramatic drop at age 50. Another guess, there are more playing ages 40-50 than "1"-10. Of course nobody will likely be playing at age 1, I just put that as the absolute. If they are playing at age one, ROCK ON! ;)
Here's a look at the guessing-chart above in terms of majorities/minorities:
The single majority: 40% ages 10-20
The 2nd greatest grouped majority: 65% ages 10-30
The 1st greatest grouped majority: 83% ages 10-40
(Ages "1"-10 and 50+ being in the greatest minority at 10%)
Person "A" might know a lot of people who are in age bracket "X".
Person "B" might know a lot of people who are in age bracket "Y".
A has no idea about Y. B has no idea about X.
Even if "A" knows kids and grown-ups and "B" knows kids and grown-ups, what both know doesn't account for the ENTIRE Global-MapleStory.
We just don't know.
But we can guess, and it's always fun guessing. lol :)