The real underlying question is why is everyone converting Troll Hearts and Blody Sigals instead of using them?
I dont convert them ... but thats because I dont buy or care about them at all.
There something wrong with the items if people see them and think "Yeah! Trashy items to convert!"
I see trashy, cheap items with limited use, but an alternative, possibly more effective use as well. Sometimes I buy bloody sigil (+10hp / -20% damage, right?) to be able to take an extra hit on a higher level monster, and then convert it soon after. So I both use the item and get the conversion bonus.
Also, it makes you somewhat glad to see these lesser-tier items taking up otherwise valuable shop space.