I think he is not one real person. There must be a group of people who is coordinating this system like anonymous. But it is right that these people have lots of coins worth some billions in total.
That issue has been discussed here before, we don't know if Satoshi Nakamoto is a group of people or just even a single person.
No doubt if the founder had a lot of bitcoin because of he/they are the first who spread this kind of digital currency and now it has still existed and very well known currency.