Yes, The form of RP must be kept, and sure, demanding upon the role of your character is cool.
But asking for more than 10 million on a 2.7K transport? or All of someone's ore just because you're too lazy to do it yerself? No, not cool. That's Meta-gaming.
If I can demand as much as my role allows, I'll say my role is a psychopath that when he sees money, he wants it, he'd kill for it. Then I'll demand any trader I see 30 Million. No money? PEWPEW.