Salem

Buyable In Boston : 100 silver
Use : Holds 8 worms
How To Use : Right click it with a worm to add the worm to the jar, right click the jar to take out a worm.

Simples

Something to hold worms would be nice. Maybe a bait bag we can make using leather or cloth.

or implement digging up and heating up sand in the smelter till it is glass and shaping that glass into jars(also for jam)

That would mean sand and digging would have to be reworked. As of now you hold dirt over your head and can only load it (like fuel) into trough etc. To be able to put it into a smelter/kiln/etc would mean dirt would have to be in your inventory first to put it into the smelter/kiln/etc. Instead of changing a system already in place, it could be easier to just add a recipe. However, a whole glass profession could be implemented one day with maybe beach sand, kiln to turn into glass, and some sort of fire torch object to shape glass into glass panes (instead buying them in Boston), glass jars (worms, which still sounds weird to me putting worms in jars), and other glass endeavors.

Glass making sure would be nice, but otherwise I would go with a worm bag which can be crafted, I have too many worms to even considering spending 100s for a little jar, unless it held say 50 worms.

No doubt everyone who has terra-formed even moderately will have most of their storage dedicated to worms, which is ridiculous! Something needs doing about it for sure.