Most of it probably. And the more tokens you have the easier is to put majority of them in the stake, also any fees are irrelevant on the large scale operations

Most of it probably. And the more tokens you have the easier is to put majority of them in the stake, also any fees are irrelevant on the large scale operations, unlike the small transfers. So The biggest holders of tokens become the biggest stakers, and thus become the biggest earners. Since the rate of token accumulation will only increase because the of compounding of the tokens in the stake (new profits will be staked too).