I suspect it's because it takes some work to collect the guano + it speeds up growing times on herbs and crops. yellow crumb takes longer to grow + when you eat it, or imbibe in its essence, it speeds up learning time for whatever skill you are learning. Which is awesome when you have a skill that takes 52 days to learn.
At Herbalism 3 the avg shuck will give you 2.4 seeds per flower. Meaning 130 currants per flower is a fair price. IF you only have H1 or 2 you'll prob make more selling the flowers on auctions or towers rather than shucking yourself.
elf, the question was why it was worth so much. telling someone that it sells for a lot of cash doesn't explain why it's worth so much. telling them it gives you a lot of IMG when donated does explain it in part. just be nicer next time, please.