It's a problem of fairness. Satoshi released Bitcoin publicly and only then began mining coins, just like everyone else was potentially able to do. It's hard to begrudge him from using his own invention, after all! Whereas pre-mined cryptocurrencies make others feel cheated.
I understand the fairness argument, but I wonder where the line is drawn between pre-mine and low-key release. Just releasing the client doesn't seem like it'd be enough to evade criticism if the practical effect is the same as a pre-mine (i.e the creator gets a huge head start before people start to catch on).
Before Satoshi's invention the concept of pre-mining didn't exist. I think the inventor of the worlds first decentralised currency is allowed to do whatever he wants. If you dont like it, make your own currency and stop bickering.
Huh? Of course he is allowed to do whatever he wants, the nature of Satoshi's prerogatives are not in question here. My point is that there's very little practical difference between pre-mining and early-mining during a time when the currency is basically unknown. It's not as if it's a trivial amount of coins either, Satoshi's stash completely dwarfs the holdings of every bitcoin user that has come after him, so it's hard to just write it off as blockchain finder's fee.