On the progression servers (Ragefire/Lockjaw) these give experience, gold, decent faction, and various small tattered gear.
For a single character, giving 30 belts to Canloe takes you from 0%, to 5% in to level 5.
For a group of two (both starting at 0% experience) in which each turns in 21 belts.will go all the way to Level as well (about 3% in to level 5).