I wouldn't really call it "mob-like", but when someone gets access to extremely hard to find seeds, they're not going to give them to just anybody. If rajah seeds were publicly offered, they'd be snapped up by everyone who has any clue what a nep is in a matter of minutes. Tons of people have rajah, but I can think of maybe 10 people on the planet that have the conditions to care for one long term.
No use wasting something rare. If 99% of the people that wanted rajah seeds got them, it'd be just that - a complete waste. As I said, hardly anyone (comparatively) can deal with the plant until maturity.
Kinda the same thing with other species, but I guess more with rate. Why give them to a n00b who might not even get any to germinate, or will get very low germination, when you can give them to a good grower you know can get high germination and also care for the resulting plants properly.
Some call it snobby, but realistically, that's what is known as responsible.