Does using china glass for part of butter color keep cost down?

The main purpose of the China base is that the colors are pretty, and stable and provide a great base for an inside complementing or contrasting color to the butter.

It does help keep the cost of Butter glass affordable, as there is no color that is this affordable or is there any American color company that makes tubing?

can you smoke hash out of a ssv?

Yes, if it is old school hash, it is easier.  Best to mix a little with some herbs to help it stop from falling through the screen.

New style hash, called dabs are best done on the dab dish.