Worms are commonly sold by count or by weight, while this usually isn't a bad thing in itself, it can be hard for the customer to verify if they have received what they bought. Worm mixes are another to package compost worms that requires much less effort from the worm farmer, that is cheaper and makes life easier for the customer who does not necessary need an exact amount of worms but would prefer something that is more efficient for starting a new worm bin.