Highrollers are not interested in affiliate cuts generally because the amounts they get back seem to be significantly smaller to them and not worth the effort.
If a highroller wagers 1000BTC on a dice site, he would likely win a lot or lose a lot.
If he does take the time to sign up using the link you give, he would be gaining 1000BTC * 1% * 10% * 50% = 0.5BTC.
Suppose he loses all his bankroll what is he going to do with 0.5BTC?
Suppose he wins a few hundred bitcoins, does it actually make a difference?
This is why highrollers tend to stick to 1% flat edge sites and does not leave to other sites like say Betterbets (which has a rakeback system) or Rollin (which has a levelling system and weekly wagered prizes). So they tend to stick with the site they are comfortable with which is why Primedice remains the market leader by large.
Another way of understanding it is, let us divide people into two, one who actually prefers a 0.7% house edge over 1% etc. and the one who is not. Highrollers beyond doubt falls into the latter category. The former consists of people ideally wouldn't bet in the first place because it is negative EV.
tl;dr Highrollers are generally insensitive to variations in (effective) house edge (to a level).
thats what I think.
your answer is totally correct cause whales don't care and they afraid to meet scammers, they will feel unhappy if their uplines won't pay them, it is one reason imo.
the other reason i cam up with is that nobody or a few guy is willing to be referrals cause they don't wanna let other people get free money, like me, i never wanna anyone makes money from my losses, i would feel my uplines wanna me lose money, feel weird.